I love playing with Thor - particularly when he's below 50% he speeds things up so fast and is fun to play - but I may well have quit this game if it wasn't for Hawkeye. He's just so much fun to play - spamming arrows out there and blitzing the enemy. He even makes other characters with CDs a lot more playable - before Gambit my go-to team for Mystique LRs was Hawkeye/Thanos. It is a thing of beauty to have a protected "shapeshift" tile and have a "Come and Get Me" tile that goes off about 80% of the time. Alas, required Gambit kind of destroyed both.
<sigh> Good times...