External items granting immunities can be lost or destroyed, and other resistances could be easily lost through pools. Immunities received from crowning are intrinsic and last forever, which makes sense thematically.

That's right, but right now the deity won't give you =Acid if you wear your black dragon scale mail even though it could be lost or destroyed. Then, if you also wear your crown of fire it won't give you =Fire, even though you could lose the crown to the next acid trap. But then, if you have all the immunities it suddenly goes back to giving you a random one. For me that just feels like an anticlimax.
Note, that any player who wishes to receive an immunity nevertheless, could still simply adjust his equipment to get an intrinsic one.

I agree with Cactus on the anomalies of the current system. However, I feel like the more logical solution (which will naturally nerf crownings) is to remove the impact of worn items whatsoever. This way, you will get a random immunity in any situation except when you had this immunity intrinsically. Of course I like the mechanic of wearing AMW before crowning but we can all agree that it is nonsensical from roleplay point of view. Especially considering that AMW is guaranteed. So what if =Cold is mostly useless, tough it out.

Some extra checks to be introduced:
1) You can never get an immunity which will be overwritten by later class power. Thus, Weaponsmiths would be barred from receiving =Fire if they crown before level 25, because deity is able to feel the PC potential. Seems absolutely plausible to me and doesn't cheapen class powers
2) If you manage to get all immunities intrinsically (or some set + later potential class powers), you will get the aforementioned bonuses proposed by Cactus.

Weaponsmiths get =Fire at level 32... honestly, I'd rather waste the level 32 class power and get =Fire in time for the ToEF rather than making it unavailable for crowning. I agree that removing the impact of equipment makes sense.

2) If you manage to get all immunities intrinsically (or some set + later potential class powers), you will get the aforementioned bonuses proposed by Cactus.[/quote]

AFAIK there is no way to get intrinsic =Cold except by crowning (unless there's a new drop in the Ice Queen area...) and no way to get =Fire if you aren't a weaponsmith other than crowning.

For the idea in general, I don't particularly like the idea that wearing the ring of immunity should grant you two or three intrinsics, especially a selection of ones that are individually better than the immunities.

No, that's fine as it is. It's one of those quirks that would have taken us a long time to find if we hadn't taken the easy path and read about it online.

Aren't weaponsmiths the only class that can achieve this? (At least in 1.1.1)

=Fire is indeed exclusive to weaponsmiths. ToEF can be done with fire resistances, frankly I don't see the deal. Getting a class power that is absolutely useless (since immunities don't stack) is worse even than making rations from corpses.

I disagree about this RFE. The current system is fine as-is. I think the deities have the flavour of being a bit lazy and not care too much even about the champions. "Oh ok, he has cold immunity, let's give something else" and just not give a damn on why that immunity exists. "Oh, he has all immunities, so I don't have to bother." It goes with the flavour that precrowning gifts can be awesome and they can be completely useless or even harmful (BToA).

I don't see Ancardia's gods as helpful and friendly ones, they are egoistic and hedonistic entities.

From a roleplaying point of view, it would be plausible the opposite way.
A nice god might say 'oh hi, I notice you're wearing that crown of fire all the time, you obviously really need fire resistance, here you go'. :D