Lance cav is actually quite balanced atm, at least when it comes to fighting melee classes, you just gotta be smart about your angles, speed,manouvering and picking your targets. The main issue though is the damage that ranged (pretty much all of them) classes do to cav.
My padded warhorse dies from 2-3 shots max, so when i charge at a pack of archers i'm basically taking one for the team cause they all concentrate on me, plus when (no ifs) i get dehorsed i get to annoy them some more as a shielder.
Overall, the class is not as fun as it used to be ( i loved cav fights back in the days with crazy angles), but still very viable, although kinda squishy.