I think Hachi, Grit, and Kanbei are top tier for AW:DS with Collin being a close 4th but not quite there. I play Hachi and yeah.... he's gay. My friends and I actually ban all four of those characters when we play. When we do ban those four, I play Jess or Sensei (who makes it no longer possible to play on large maps). Out of curiosity, is it standard to play with or without CO Powers? Some characters are useless with them off, but at the same time some characters just have ******** CO powers (e.g. Hachi xD).
I think rockets are only too good on maps that are entirely based on land. As soon as you throw in aircraft and you have to add anti-airs to your screen or missiles it becomes too costly.
But yeah... some maps are ******** and it becomes a stalemate.