Basically everyone in MTMTE, including Megatron and (the more of a guest star) Prowl, and particularly all the Scavengers. In most cases just by giving the characters time to have personalities rather than just gimmicks/stereotypes.
While I agree Blaster has been under used, rebelling against the leadership on Lost Light, in this case Rodimus/Megatron, is not that different to rebelling against the leadership in the comics (Perceptor, Grimlock).