The staff of the magi is pretty much equivalent to the staff of the archmagi (pretty close damage wise, +3 PV on the staff of the archmagi, not uncommon to find +9 Ma ones). So, the staff of the archmagi needs a pretty big change. Any of the above changes will help, but it also needs to be made like 5d5 at the least. You can't spellcast ALL the time.

A spellcaster with this thing in his/her hands will be casting spells ALL the time, even when not necessary.

I think a big mana increase (+18 or so) is probably fine and giving it maybe better DV/PV like [+11,+6] would probably make it worth a look for casters. Giving it the equivalent to the "of power" suffix (+20% PP) would be reasonable as well, I suppose. Mana doesn't actually have a huge effect on luck--even +18 mana is weaker than if the artifact gave +Fate, IIRC.

Increase of PP and decrease of spellcasting costs sound just like what an archmage expects.
For me, DV/PV will never be a determining factor of whether or not to use the staff - any characters that might benefit from it, already use offensive magic so they are pretty much on a permanent coward mode. Additionally, no staff will ever beat shield+spear setup, for many reasons.
Melee combat viability of this staff will always be questionable as long as the damage output is near non-existent.
I always felt that the idea of using a staff by pure or near-pure spellcasters was because it granted some inherent magical bonuses rather than granting melee combat value.
Right now those bonuses are quite pathetic.

I'm all for making it even 1d2 in terms of damage, as long as it actually grants magical boon to live up to its name.
Making spells cost 50% less and increasing base PP by one third - 33% - is certainly going to make it worthwhile.
Mana attribute fortified by 15 points would be very welcome too.

There would already be significant DV bonuses on coward with some weapon marks in place so it doesn't really need a better damage dice.
It's not a club, it's a powerful, magically enchanted artifact for users of the arcane.
Barbarians and the like should just use a two-handed sword for the damage output it grants and any potential offensive additions (thunder/frozen/flaming etc).
Similarly wizards should use a staff to cast powerful spells, not bash skulls with it.
I have yet to see a YAVP where a wizard uses a staff for the majority of the game.
For all intents and purposes, AotME is better than any artifact staff in the game.

..I've completed the game only ever using an eternium-shod quarterstaff for a melee weapon, on a Mindcrafter [which presents a lot more problems than trying to do it on a Wizard since you actually have to use it, a lot]. But only people looking for a challenge would ever do that, so of course you're not going to see a YAVP where people used staves.

Anyway, no character can cast spells all the time (unless the staff of the archmagi is made super-duper overpowered and dumb, which it shouldn't be). The damage should definitely be increased so that it does more than 7-12 damage on average [before bonuses]. That's an absurd amount of damage on any artifact you're supposed to actually use. 5d5+2 (7-27) would be a very nice boost that lets you actually kill goblins on D:40.

While some of the buffs are worthy anyway (definitely up the Mana boost), I think the real problem here is that wizards are expected to have staves, yet don't really get much intrinsic benefit from them. The loss of a shield is problematic when trying to train up the skill necessary to actually use staves effectively, and a wizard can't really hang around attacking low level monsters trying to train up the staff skill.

So here's an alternate idea: much as how whips use Dexterity rather than Strength to determine damage and to-hit, perhaps staves could use Willpower to alter defensive boosts? It could make staves more appealing to high-Willpower races/classes, with wizards, healers, mindcrafters, monks, and priests being most benefited by this connection.

Think about it, and you'll see why it makes sense - unlike other weapons, the staff is naturally suited to blocking and parrying. But much of this requires intent, hence Willpower.

If there were also a boost to to-hit and damage with staves based on Willpower, it would then make it somewhat easier for classes that already use Willpower a lot to actually use staves. And then the various magic-focused staves would also become more useful to those classes.

Essentially, you would want it to work out so that, for a level 1 wizard with, say, 20 Willpower, using a staff works out better than wielding one shield (say, a medium shield), but not as good as wielding two such shields. That way, the wizard is encouraged to use the staff, but it's not overpowered. Note that I'd also suggest that it boosts PV based on Willpower (in this case, picture it as the wielder catching an attack with the staff, but having to hold off the attacker's force using willpower; without enough willpower, the attack will get through, but weakened).

i've played characters through without using melee at all. though its a bit harder now with ID scumming a bit harder.

i like the idea of PP boost + spell cost reduction. It would be awesome if the staff was like a genuince, caster staff , ie: you would NEVER use it in combat. So those kind of boosts would make sense. about +18 mana is about right too considering the ToTRR boost.

Since this was an early prerelease change, I presume you mean in 1.1.1. The main thing that makes pure casting impossible now is that HP casting kills your stats, so it's something you never use unless you're in danger of dying (or similar). So, it is currently "impossible" (in any semblance of normal gameplay) to spend the entire game after crowning casting.

The OP is not proposing that the staff be made auto-cursing. It is really simple to swap weapons in ADOM, I do it all the time. If I cast I wield a Wi boosting weapon, if I melee I wield a good melee weapon, etc.

The OPs suggestions would make it almost(if not all) possible to cast all the time for a wizard at least. Is this good or bad?

Aielyn's suggestion sounds viable.

I am feeling a bit confused though, because, my current wizard only wielded his starting quarterstaff up to about xl 16. It did not feel too inferior a weapon on the starting levels of the high king's tomb. Where he went directly at the start of the game.

Look, I'm not suggesting the staff be made the axe of the minotaur emperor for pete's sake. A reasonable damage (all, I'll note, not even equivalent to eternium-shod quarterstaff, I think it is about adamantium-shod level) would make the staff more likely to be used and should be included in any talks of making the weapon useful. Personally, I think switching weapons is tedious and I hate having to do it - and I don't think ADOM should encourage some stupid min-maxing tedious play like that. Make the quarterstaff usable as a weapon [not good, not great - usable], it's not a huge damn request and will boost the staff's worth a lot.

I assume the OP's suggestions are all separate, not intended to be all implemented in one - that'd be nuts. Of course a wizard shouldn't be able to cast the entire post-crowning game.

We can't remove something from the game that is in every facet of it. That would mean one has to make every piece of equipment a good option in every situation, might as well remove equipment, elements and special attacks from the game then. Actually, you will have to remove the entire game from the game.

The staff of the archmagi is an oversized wand, that is all. It is meant to be wielded my magicians that kill most things with magical attacks.

e: As I've said in another RFE, staves should give a Willpower boost. A spellcaster would feel much more confident channeling magic through an oversized wand than a spear for example. Or so it should be.

We all agree *something* has to be done about the staff of archmage. When my wizard gets it, it is discarded immediately. I don't ever remember using it, not even once.
As for staves in general, the moment I get an orcish spear on my wizard, I ditch the original staff, that's how useless staves are.
Damage-wise it's almost the same as the spear, but with a spear you can use a shield and eventually get enough marks to have superior dv.
Early DV bonus of shield+spear combination is much more useful than the eventual DV bonus you get at higher skill level with staves.
This is the first point: combat viability of staves is poor.

Second point: It's a wizard's weapon.
It may not (or should not) grant some tremendous combat upper hand but it should at least be ok.
Staff of Archmage is very, very poor in that department, on par with random starting staves that occasionally have a bonus to damage roll - 1d10+3 or +5 is not unheard of.
Staff of Archmagi should provide at least 50% more melee damage than that, which boils down to giving it around 4d5+X or 5d5+X damage.
Here's the point where we could dispute the X value. It might be determined by Wi attribute to some extent, for a total bonus equal to half the Wi value.
This would mean that the more powerful (in the magic sense of the word) your wizard becomes, the better the staff performs in combat, as its nature allows you to channel your spellcasting power through it into physical force and smite your enemies.
+20 damage for wizards with 40 willpower is not unreasonable, it's an end-game value, for an often late-end game crowning gift, assuming you're not playing an actual archmage challenge, which is fairly rare among players.

Third point: Magical use. I thought it pretty obvious that the name implies this but apparently some people do not see that.

Wrong.
First, it's a crowning gift. That means it's a unique item and given the circumstances in which it's obtained, it's supposed to be super-powerful.
I rarely find this item in my games, once in five characters that close the gate find it. This implies that no amount of buffing it will disturb the game balance in any way.
Some of those characters are melee classes that already have a powerful weapon (like my recent monk that got wicked mithril spear of devastation, you can't beat that with any staff, no matter what) and will not consider the staff from combat point of view, much less from a magical one.
Only 2-3 classes will truly benefit from extensive buff to the staff of archmagi and that is perfectly ok.
Second, it's not a wand, not even close, it doesn't let you cast spells you don't already know and it takes the weapon slot. Clear enough your statement here doesn't make sense.
It would actually be nice if it could behave like a wand in some fashion.
I won't discuss the magical side of staff of archmagi as I already said a few posts back how I see things.

Well, I think that the creator of the staff of the archmagi would have probably put some sharp metal bits on the one end and called it the halberd of the archmagi if he/she wanted to create a good melee weapon. Somehow I get the impression it was mostly created to be a good item for a mage to use to channel spells through.

You're right. The problem is that it fails even in that department. It's basically useless no matter how you apply it.
Also nobody is saying anything about it being a good weapon.
It should not be a good weapon but neither should it be an absolutely abysmal weapon as it is right now.
Good weapon would be 6d6+something.
5d4 or 5d5 would be OK. Not good but not terrible like right now.

It should be abysmal weapon IMHO.