Being forced into classes I don’t won’t to play

Broaden your classes. If you're seriously getting upset because you're not getting your way when you join other people's lobbies, have you considered the following:

Not whining - It's odd that you're leaving games because you don't get to play what I assume is Tactical

Hosting your own lobby - Then you could play the class you want

Refunding the game - Might not be the game for you

If your thoughts are truly " I can’t play as the class want I’m leaving game part way though so I assume disturbing others experiences. 5 games in a row I’ve not been able to play really starting to feel like a waste of money with a short campaign" then brother, I don't know what to tell you aside from "Don't let the door hit you on your way out."

Note: It's not that you've "NOT BEEN ABLE TO PLAY" you're literally choosing not to