I don't know if anyone knows any good mods out there for Lionheart...
But for those who played it; found; or heard of any good mods, can you mention and link any here?

As far as I know, Lionheart either doesn't actively support modding (read as: downright hostile to it), or doesn't have any mods.
I've seen one or two on Filefront (www.filefront.com, then search for Lionheart in the search engine), but that's it. And I don't know that they actually did anything.

I'm working a mod that adds new perks, new traits and new clothing colors, i'm having a hard time trying to make items though...........
PS:sorry if necropost :P

Unfortunately it's highly unlikely. First of all, the game was never at all popular, which meant there was never a really a modding community around. Plus, most of the game is pretty empty. Once you leave Barcelona, there isn't much to do other than hack and slash. Modding the game in this case is either pointless, because there isn't much content, or would be a huge undertaking, if you planned to add extra content

10 years after release , people still make mods for BG with the most famous original AD&D modules (A/L/G/D series...), they make all this from scratch with Infinity Engine community tools. I suppose that what's lacking for LH are those tools ...

L:LotC uses Velocity Engine and SPECIAL rules so none of the IE community tools could be easily ported to support it. Most likely they would have to be writen from scratch, not to mention the need of reverse engineering all file formats and scripting language. WeiDU could probably be ported (it's used in some arcanum mods) but understanding of file formats and scripting languege would be needed for that to be possible. The simply is neither interest (it just isn't that good game) nor incentive (L:LotC being only game to use Velocity Engine AFAIK) to make the tools or mod it.

Scripting is sufficiently easy - at least as long as perks go. Race properties seem to be hardcoded somewhere... just need to poke around a lot.

Perhaps the only thing to be worried about is that Velocity Engine / Lionheart uses Granny 3d format it seems, it's pretty closed but there are viewers and OBJ importer/exporter.

By the way, made two tiny mods for Lionheart just a couple of hours ago, they're on ModDB - Scion of Lionheart and Learnerheart. (Gameplay tweaks mostly.)