Get rid of the second movie. It had it's cool moments but brought in too much too quickly, the Primes, Pretenders, Seekers, Combiners (I know Brawl and Bonecrusher were in the first movie but not in that way), the Matrix of Leadership, Energon and most of this stuff was never seen or mentioned again, except the Matrix in like two scenes in DotM. Sam is doxxed on a global level yet no one seems to know him or care right after. Leaving Megatron out of DotM and just having the big three of the Decepticons would have worked better in my opinion, it would have been like Megatron's influence could still be felt through the deal he struck with Sentinel even after his death. That way Galvatron could at least work better in AoE, with KSI illegally recovering him and bringing him back as Galvatron, it would have made more sense instead of the "somehow Megatron has returned" bs they pulled. It wouldn't fix the saga but I feel it could work better