is there any that make sence and how would i had class levels to orc's and such?

Simplest solution would to give some action cards to the monster (or maybe talents). Well actually I suppose just increasing the A/C/E values would be the simplest option would it would not change the flavor of the creature. Adding the right sort of action cards would effectively add a 'class' to a creature. For example a goblin with the Backstab card becomes a bit of an assassin.

You could always modify the A/C/E pool to only allow a monster to access it in particular situations. For example if you have a creature that you want to be dangerous if cornered you could give it an Aggression Budget of 2 with 4 extra points it could use if it was ever trapped with not obvious exit. That way you make it tougher and you give it a bit of character.

I think since the NPCs work differently from PCs, you should take the easy way and don't build them using careers and etc. Take a basic monster, modify it's ability scores, wounds, damage, soak, defense, A/C/E budget, and give him some new actions. Far easier, than the D&D3e way - man, how I hated building NPCs in that game...