I'd like to see a series where Optimus Prime and Megatron are the supreme commanders of their factions (which is most continuities, granted) but they only appear in the first episdoe and a few guest shots, handing off an assignment to one of their task forces, and the series focuses mainly on the task forces. That way, Optimus and Megatron would do enough to justify toys and be around but not the main focus of the series.

 

If Optimus Prime wasnt the leader then it wouldnt be Transformers  

 

Personally, I'd like it if they returned to the G1/Beast Era universe to fill in the gap, because as far as I know, we never received a proper end to the Great War, just Galvatron floating around in Scorponok at Rebirth's End.

It could be worked so that all that really needs to happen is a reformat of all Autobots and Decepticons to be used so they have new alt modes.

Besides, it would answer loads of questions such as how the war ended, what happened to Galvatron, how the Maximals and Predacons arrived, etc.

That or do a show that's set on Cybertron as an official G1 prequel (not sure how interesting that'd be because creativity is limited to maintain continuity (or some semblance of it).

 

I get the impression that's what comics are for.

Only other idea I could think of is Optimus as a mentor/guru type grooming his replacement, in an Obi Wan Kenobi/ Batman Beyond sorta fashion.