What is the best BG2 mod out there? I want to add on to ToB and play something different...Any suggestions on the best one to play?

This is discussed pretty often and of course everyone has a different opinion... so if you run a few searches in the BG2 forums you should get a lot of results. Here's one to get you started: http://www.sorcerers.net/ubb/ultimatebb.php?/topic/10/2526.html

Unfinished Business is the best of course.

In my current game I added Baldurdash Fixpack, TextUpdate, D0Tweak, G3Tweaks, Oversight, Ease-of-use, Weapon Upgrade, Banter Pack, Flirt Pack, Revised Hell Trials, aPack, NPCKit and NMBeauty before thinking of anything else.
I put in the Expanded Thief Stronghold, if I would be getting it and love the DGItems mod since it adds a CLUAble potion bag.

I hate the HappyGroup and concurrent romances mods. Cleric-Remix really scared me and SPCollection seemed overpowered. Chole was also an unsatisfying mod.