I have put countless hours into Morrowind with a ton of mods. Some were balanced like backpack mods, light mods...etc. However, I'm sick of so many mods and started Morrowind with just bloodmoon and tribunal again. Can anyone recommend a few of your favorite balanced mods?

http://btb2.free.fr/morrowind.html

The majority of mods are balanced, because an unbalanced mod is (usually) not as fun or just plain silly.
Unbalanced mods are usually easy to identify by just a quick look in the CS (overpowered weapons/enemies/cheats/etc).... so, I'd say use the mods you remember liking and avoid the ones you consider unbalanced, because the list of good balanced mods is enormous.

Now if you're looking for a mod to extensively re-balance the entire game, check http://planetelderscrolls.gamespy.com/View.php?view=Mods.Detail&id=7904.
The link OnmyojiOmn posted is also good, if you want a collection of mods that have been approved by one modder as balanced well with the game.
:)