Carsomyr Magic Resistance Tweak
First, a hack to make Carsomyr's Magic Resistance additive, rather than setting it to a flat 50%. Probably not what the devs intended, but I like the convenience of not having to re-equip items constantly to boost it above 50%. (Plus it allows it to stack with any innate MR a character possesses).
I also altered its dispel effect; the +5 version works at level 20 while the +6 works at level 40 (because 30 is pretty much useless in ToB).
Bootleg Carsomyr (aka Purifier)'s effect has been similarly boosted.
Download the Carsomyr Tweak
Jester's Chain Fix
Next, a tweak to make the Jester's Chain actually useful to the class it's seemingly intended to be used by (Bards). This makes it so that it does not disable thieving abilities or magic spells while equipped and grants a +3 bonus against missile weapons, giving you a legitimate reason to consider getting it. I applied the usual thieving penalties for Elven Chain to it as well.
Download the Jester's Chain Fix
Aslyferund Elven Chain Tweak
A tweak to make the Aslyferund Elven Chain +5 slightly more useful. 0 AC is nice, but immunity to normal weapons really doesn't do much for you in Throne of Bhaal. So I gave it a couple of abilities useful to Bards and multiclass Mages: a passive +3 to Luck and two extra castings of Level 2 and Level 4 spells.
Download the Aslyferund Elven Chain Tweak
XP Cap Tweak
This simply raises the experience cap for multiclasses to 16,000,000 (for duals) and 24,000,000 (for triples), allowing them to reach 8,000,000 experience in all of their classes. Not the most elegant solution to this problem, but it should make small party/solo runs a bit more viable.
I've also raised the experience caps for Mages, Paladins, Druids and Rangers so that they can reach level 40 as well.