The problem with the new Megatron is that he's created with Takara's new shift to toon accurate MP's. As such he looks a little off with Optimus which was made years ago and is a sort of an amalgamation of toon/toy/realistic truck aesthetic.

This is probably why a lot of people really like Despotron as he fits better with prime and people seem to really like roided out Transformers for some reason. Personally I'm happy with how Megatron looks and Takara's new focus as I grew up watching the cartoon and remembered being disappointed how the toys only resembled their onscreen counterparts.

I'm loath to admit we need a new Optimus as he's been done so much but he does look very dated compared to Megatron.