This game felt so wonky in the beginning, but now I'm really comfy and confident with all the mechanics. This game is a blast to play.
I've currently learned how to play Spring Man and Master Mummy to a relatively high degree. I love them both for different reasons.
Spring Man's ability to counter any punch seems extremely strong. He can just wait and react to any punch then follow up with his own. He's particularly strong in close combat for this reason.
Master Mummy has a great keep away game. I like to equip wind type arms to keep my opponents at length. This allows me to replenish health and react to any throws that they try to catch me with.