I'm playing through this with a little bit of roleplaying added in. I am only using gear that I found in Ironfist or in the dungeon itself, outside of a dozen restoration potions. Now, I'm playing version 1.34, so I have level 5 ability in lightning and meteorstrike, which I might not be able to have if I played the Gog version.
I'm a mage, so I'm not super-dependent on gear; as long as I have potions. I'm finding the deeper level(s) of Iona's to be quite challenging this way, and I'm just on normal. I pretty much accept whatever I find loot-wise; at least outside of bookcases and known good items.
I'll save before every bookcase and reload till I get one spellbook/bookcase area. If there are 4 or more bookcases, then I'll reload till I find two good books

There are a few spells that seem to do nothing. Anything that raises might has no effect, including potions.
I reload on special loot items too, like a certain bat in the catacombs, an amulet nearby, etc.
I just love this game!