Suggestion
Some non-guaranteed items are too hard to find without using a wish, which is something not justified by their degree of power - they aren't exceptionally useful like an AoLS or ring of elemental mastery for example, or just are different versions of another more common item.

Some that spring to mind are:
* Torches. Even though they're DL1, it may take a long while to find one if you don't start with some. On the other side, the otherwise useless tinderboxes and boxes with flint and steel necessary to light them are much more common.
* Amulets of hunger: they're too rare for a "bad" item. I can't recall the last time I found one.
* Rings of gain attribute: they're way rarer than other, better rings. Not exactly overpowered with a typical bonus of +1, either.
* Rings of the clear mind: rings of mental stability are more common, do the same thing, and increase PV and Le slightly.
* Robes of invisibility: I don't know how cloaks of invisibility, which occupy a less important armor slot, are much easier to find than these.
* Bandages: the solution to bleeding is to 'a'pply First Aid or wait for it to end, because these are too rare in the early game if you're not a Healer. I think there were some guaranteed ones from Thrundarr, but PCs at that point in the game probably don't need them anyway.
* Daggers and spears of returning: for a returning missile doing less damage than the common boomerang, these seem to be exceptionally hard to find.
* Missiles made of the higher metals: it's easier to find the tremendously powerful slaying ammunition than a stack of adamantium quarrels, for example.

Maybe also:
* Anvils
* Figurines of wondrous power
* Fletchery sets
* Stethoscopes
* Spider bread

Why it'd improve the game
More people would get to use these, or even know they exist without reading spoilers.

Notes
N/A