Sorry my picks didn't copy over
So we can start with some Autobots.
Springer, the all around jock
Arcee, his on-aga-n off-again girlfriend.
Hot Rod, the guy who has a crush on Arcee, and she barely registers his functioning.
Grotesque, who Arcee doesn't want to touch at all
Sureshot, who is tired of the high school drama and can do it better by himself than combined anyway.
From the Movieverse
Jazz, Jetfire, Wheeljack, Hot Rod, and Strafe. Mostly because none of them are ever in the same films. Most of them die in their respective films Then having a combined form is absolutely ridiculous.
I'm going to break my own rules, we need a cassettecombiner. Not a two parter, but Rumble, Frenzy, Ravage, ratbat, Laserbeak, and Buzzsaw. Slugfest can form a shield, and Overkill a gun. This isn't one of the silly ideas, I kind of like the concept. Soundwaves cassettes combined can measure up to Soundwave...