Im unable to find any big mods with useful new armor/weapons... does it even exists ?

I found stuff with Lich King and Sauron, but i think is pretty lame

Have you considered one of the overhaul mods like Frans or OOO which adds tons of new items to the leveled lists?
If not look for Real Swords and Armamentarium, both found on TESNexus.

More than enough to be found at tesnexus.com (unless you're not looking for super revealing female outfits, SNAP!). Keep in mind that several armor compilations are sold through custom shop mods, so also browse the mercantiles category.

So you basically buy your armor with these mods ? Do they have useful stats ?!

It may be fun, but it goes against the dungeon crawling and find loot feel...

Armamentarium is the biggest mod I know of that adds new armors to the leveled list, so you can get them from dungeons. They're mostly recolors of vanilla armors though.

Sounds like you should check out OOO. It has lots of added armors/weapons, not only in leveled lists, but also handplaced in dungeons, making exploration and dungeon crawling more "meaningful" and fun than with vanilla's approach with random loot everywhere. Of course, OOO is an overhaul so you should check out its readme and see if you like its other changes.