While they don't need to go back and rehash G1's plot, I'd love to see a cartoon style similar to G1. Animation quality along the lines of a Gundam or Macross series. Honestly if they wanted to these days they could do a entire series in the same animation quality as the G1 movie. Something of the quality of Korra or the recent New Thundercats series. CG is holding back the character amount and you could have more characters that appear short term and a larger army cast in a traditionally animated series. That was one nice thing about Animated was huge casts and background cameos even if they never spoke a line of dialog. Heck pull a Warner Animated and release a straight to video of something like War With in to appease older fans.