I don't understand how anything in this type of game is "overpowered". If you don't like it why the heck would you use it?
Seriously, if something is "overpowered" in Skyrim you have the option to not use it.
Battlefield or COD have weapons that are occasionally OP. That is because people exploit it!
Oh god don't, I have Famas moans etched into my brain

I never got the big deal about that gun, the only way it was superior was if both combatants fired at the precise same time - that never ever happens.
Anyway, it was about 10th on my KDR list if I remember correctly, the commando was top and my favourite weapon was the HK21 (find another relatively high prestige player with THAT on their combat record

)
On topic: I agree, OP is a completely different concept in a single player game. Especially one where you can tailor your effectiveness. If we were RPing, the crossbow would pretty much one-shot everything.