Yeah TF2 is really fun to play with friends, but I'm more of a csgo guy. I see it as you're either one or the other.
Whenever I play I always choose the engineer because you can mess with other players easier. It's like the troll character :D
I used to enjoy TF2 in the old days when there werent a lot of other big multiplayer games around that you could just hop into casually besides counter strike but now that the genre has grown a lot I lost interest (like many more I believe).