but for once I want to do some pvp alongside some pve.

What classes are at least decent at both?

locks are good at both
hunter good at both
rogue good at both

warrior, ret, hunter

Hunter master class

Expansions and patches bring nerfs and buffs. Every class plays different and it's all about preference. Shouldn't really play a class because it's the "best". Play it because you enjoy it because all it takes is one patch to nerf it to the ground. Also, I will say Rogue and Hunter because I enjoy playing theses class

Well said.

pretty much why ive played a warrior above all else since near the end of vanilla.