After having done a lot more pvp in modes outside of Arena I can tell you...
I suck haha. It seems I perform the best when in Arena maybe because it's open and team fights. I guess there's no need to beat myself up completely, I won a few good Jousts too. I like Arena and Joust. Really hate Assault and that saddens me. It's definitely no ARAM. The trouble in general I am experiencing in this game is that everything dies SO FAST. I get that it's intentionally a fast-paced MOBA, and that's kinda the point. This game has a knack for punishing your mistakes. I've seen people blow up at level 3 with one wrong move. I think I'll stick to my mages and guardians, I do the best on those.
I'm going to continue to play, of course. It's really cool to have a MOBA for my livingroom. Don't always like being isolated in the office.