I think it's fair to say axes are king in IWD. One thing that's sort of bad is the fact that there aren't enough spells in the game (like one copy of each spell at most, sometimes some spells never drop), so it is ideal to have only one mage in the game.

well, it was a level 12/12 cleric/mage(base thaco 12).. with an 18 strength raised to 22 from calling upon holy might.. and a plus 3 weapon... that actually only took it down to about 5... but after casting tensers transformation, it dropped to -2
remember, Clerics have the 2nd best Thaco progression in AD&D.. make a cleric mage and you'll see the awesome power

as for your trouble with seeing the thacos... try getting the official patch 1.06.. that fixes the modified thaco..
you may also want to go into the game play options and turn on "to hit rolls" so you can see the actual rolls and modifiers.

I didnt realize clerics had the 2nd fastest thac0 progression.
Very nice.
Thanks for the breakdown.
v1.06 shows the adjusted thac0 in parentheses, whew