Since TF5,6,7,8 are on its way, it's time to start speculating what is to come. Marvel will definitely have a big impact on this CU in my opinion. The MCU has been so successful & if Hasbro do it right, they could easily do the same.
First of all, why is the MCU so successful? Is it because it's full of an Asgardian who love throwing a hammer all day?Is it because of a guy named Nick Fury who loves playing with an infinity stone all day? Nope. It's because they keep the suspense. Everything leads up to something. Everything all comes to together in one plot. In Marvel there has always been a big evil behind everything and his name is Thanos. Marvel has led all their films to a villain who they can't wait to see in action because they know he's bad ***. We've seen in Guardians of the Galaxy how he doesn't give a sh** about Ronan and from being threatened by the Accuser he turns him away. Why am I talking about stuff that isn't Transformers? Because in the majority of the Transformer continuitys, our mad Titan has always been Unicron. Yes, the infamous Unicron. He's the perfect antagonist for the TCU for one BIG reason: you can't just kill him off in one film. Hasbro has a tendency of just having a main villain for one film and killing him off at the end (with the exception of Megatron). If they're going to make it a cinematic universe, they'll need to make it slow, give portions of scenes revealing our main villain so they watch the next movies. In the end of Age Of Extinction, Optimus sets out into space in search of the Creators (most probably the Quintessons), leaving everyone else on Earth with a loose Galvatron who claims he will meet his advisories once more. A potential plot for TF5 could be for the first two-thirds of the film they could have it where Optimust in in space on his mission possibly confronting some enemies or even finding an ally whilst on Earth Galvatron could be in search of an army to attack Earth once again (Predacons could be good as they are a good reason to bring back the Dinobots and they give a tribute to Transformers Prime). Maybe the Autobots on Earth receive a call from outer space of another Autobots and the humans try to create some sort of space bridge under guidance of Crosshairs. It will kind of be like TF RID where you have a few scenes of Prime in space and most being on Earth for the first 2/3s of the film. Then maybe when Megatron invades, the Autobots end up using their space bridge to bring the warrior who could be Ultra Magnus (another tribute to TFP season 3) and helps wound Megatron. Then the Predacons led by Predaking could take him back to their hideout where they repair him and 'G1-afy' him to he has his cannon on his arm. Then if Optimus finds the Creators and kills them, he could use one of THEIR space bridges to quickly get back to Earth (life on Cybertrons backstory could be explained in a scene for Primes battles his creators). In the end they might find out from Ultra Magnus that there is still life on Cybertron and that he was heading there but his ship got damaged hence why he sent a distress message, so then all the bots return to Cybertron leaving the humans (with Crosshairs probably remaining so he can open the bridge for his end). (Also I forgot to mention the Dinobots could maybe appear after sensing the Predacons this time with an army of Dino's so our guys aren't outnumbered). Maybe on Cybertron there's a peaceful moment but then suddenly another hostile organisation that aren't Decepticons who invade and then the rest of the movies just kaboom!
After in an end credit scene (is they decide to incorporate one), they could have someone like Thrust from TF Armada (but one who would have a voice like The Other from MCU) flying somewhere in space that isn't explored much to a damaged, cast-out-looking Unicron in planet mode. This sets up the next few films as fans might speculate an Energon plot (hopefully we never get that) or Unicron return. When Thrust enters Unicron, they would have him speak with Sideways who is planning to revive the dark lord or instead of having Unicron damaged in space, they could have it where on Earth, the Predacons were eradicated and the Autobots took Megatron back to Cybertron and castes him out into space. Then in the end credit scene they could have Megatron floating in deep space, seeing Unicron as a planet (so they don't give it away to people who don't know about Unicron) with Megatron having a shocked face saying 'He lives.' This would also make people speculate that Megs with ally himself with the chaos bringer which can also set up the Dark ENERGON plot which they can maybe show in TF7
- Of course, this is only a though, for all we know the next TF films could be about Optimus learing to ride a pony and all that good stuff
- Also when I say Megatron I meant Galvatron (soz, just forgot about that he is called Galvatron unless he decides to stick back to his original name which is unlikely as in AOE he clearly stated his name was Glavatron)
- Also, another plot for the TCU could be the omega keys from the Unicron trilogy(which could act as Transformers's version of infinity gems lol) with Sideways as Thanos and Thrust as the Other but thats just a thought.