So they've taken care of Straxus, Thunderwing, Skullgrin (sorta), Reflector (sorta), Mindset, Windcharger, Axer, Fallback (sorta), Highbrow, and maybe some others I'm forgetting. I'll go ahead and just count Drift, because how many non-hardcore TF fans read the comics? Who is left? The only obscure character I can think of is Flame. He would make a beastly flamboyant tankformer.