My concerns about lancers being "OP" were mostly from a cavalry perspective, but I think they are in a position where they can easily decimate both cav and infantry (especially rifles, but so can normal cav). Against cavalry:
1) Lances can outreach your sword (logically);
2) Lances can stab your horse, and there is absolutely nothing you can do about it (can't block it, or evade it, if you're heavy cav, as they are faster);
3) Lances can couch you when they've stabbed your horse to pieces, as it is very hard to outreach a couched lance with a sword.
The only way to get rid of a lancer (especially an experienced one) is to work together with either infantry or another cav guy, in which one cav guy rears up his horse, and your partner takes the lancer out while he stands still. In nearly every other situation, the lancer wins.
Which is why I feel the lance should be nerfed, like (for example) having to drop the lance if you want to switch to your sword, or having the lance break after a stab, or only being able to couch.