Defeating Kahrk with a 5th-level party is impressive, since he is a 12th-level mage with innate ogre-mage abilities on top.
I should probably add a note to the readme about metagaming. In standard BG buffing your party before a fight may be necessary to survive some of the battles, and there are even NPCs who are pre-buffed. This has changed in FotD. You may have noticed that many spellcasters begin with protecting themselves, and this is a big disadvantage if you are ready to launch an attack. I have tried playing the game without metagaming, and it is certainly possible. It is also more fun since most fights are too easy if the party is enchanted by haste, bless, strength of one, defensive harmony, grounding, protection from paralysis, etc etc.
Gauntlets of Dexterity are also unused.
-Echon