Westley Weimer strikes again, this time with an expansion for Cromwell and Cespenar that enables them to upgrade dozens more items, including clubs, spears, character-specific items for Valygar, Keldorn, and Mazzy, and more...
http://www.cs.berkeley.edu/~weimer/bgate/item.html
Cespenar/Cromwell Expansion MOD released
Cespenar/Cromwell Expansion MOD released
"t's a testament to the determined RPG fraternity that a number of Baldur's Gate II mods have been successfully produced. The best can be found at pocketplane.net." - PC Gamer UK
Heh. I guess maybe Jan and Edwin could be in line for upgrades, although I can't imagine what on earth you'd want Edwin's amulet to do that it doesn't already! 
"t's a testament to the determined RPG fraternity that a number of Baldur's Gate II mods have been successfully produced. The best can be found at pocketplane.net." - PC Gamer UK
I'd like to have an amulet that lets a Mage cast one or two extra spells per level, reduces casting time by 1-4 (whatever is appropriate for game balance), and grants the wielder permanent Vocalize. Not terribly overpowered, but better than Edwin's amulet. If you want to make a really overpowered item, you could make it give the wielder permanent Protection from Evil and immunity against Time Stop.