Deadlock is really great. I like to go to the enemy base and try to 1v6 people repeatedly. I get angry when my team tries to help or pings me to do mid boss, urn or kill creeps.
Uneven matchmaking is definitely the biggest fun thief in the game right now for me - whether it's our team or the enemy team that does the stomping. It's a shame too because the close, even games are so much fun. Glad to hear it's being worked on.