I kind of suspect I'm going to look back on this in a year and laugh at how wrong it was, but hey.
1. Megatronus is going to show up again, but not as the main villain. He’s a decent major villain, but not a main villain, unless the show’s going to get a lot darker; dealing with him is too high-stakes. Good for a big climactic season finale, bad for every week.
2. Sideswipe and Strongarm are going to end up in a romantic relationship. Watch the Windblade episode - specifically how Strongarm reacts to Sideswipe’s interest in Windblade - to see some of where I’m coming from on this.
3. Team Prime may or may not appear in the show, but the comics are going to stay as their own separate thing. Hasbro’s got a good thing going on with age stratification by medium, and comics are for an older set than the shows. I think the RID 2015 comics are aimed at the now-teenagers who watched Prime when they were ten, not the now-eight-year-olds who are RID 2015′s target demographic. I also think that they’re meant to lead the teenagers from the TV shows into the rest of the IDW comics.
4. The books, on the other hand, are likely to be canon in the event that the stuff in them ever comes up.
5. They’re basically going to keep going with the Decepticon of the Week “gotta catch ‘em all” plot. New Decepticons will show up roughly every episode and new team members will rotate in and out. There’ll be some continuity, but not a ton. It’s working; why mess with what’s working?
6. At least one or two of the Prime Decepticons is going to show up. In order of likeliness for this role, in my opinion, from most to least, not counting Knock Out because he’s an Autobot now: Shockwave, Megatron, Soundwave, Starscream. Shockwave is the most likely, unless they decide that Megatron has gotten over his weird existential crisis and wants to be a Decepticon again; Soundwave is probably dead; Starscream is almost certainly dead.
7. The rest of the Thirteen are also going to show up some more, probably also in a major climax. Like Megatronus, anything involving them is too high-stakes to be a regular occurrence with the show’s current tone. (A show where a normal episode has our heroes fighting to save the entire planet is a much more intense show than one where a normal episode has them trying to capture a delusional robot tree frog who’s trying to get to Cybertronian El Dorado.)
8. Prowl and/or Ironhide are going to show up. They’re in the mobile game, which seems to be a pretty good indicator of appearance in the show; Jazz and Megatronus were both in the game first. 8b. Strongarm is going to turn out to be a massive Prowl fangirl. (Shipper 8c. Sideswipe is going to react to Prowl about the same way Strongarm reacted to Windblade, and for the same “awkward unconfessed jealous crush” reason.)
9. One or more of the current team members is going to leave. As of the end of Season One, counting the minibots, there’s nine team members (Bumblebee, Grimlock, Fixit, Sideswipe, Strongarm, Drift, Jetstorm, Slipstream, and Windblade); that’s too many. Someone’s leaving. I suspect Drift and the minibots.
10. We’re going to get a bit more backstory on the core team members and the universe. Why is Bumblebee, the famous war hero, working as a regular cop in Kaon? What in the world happened to get all the criminals branded Decepticons and shipped out into space? How long has it been since the end of Prime? Not all of those are probably going to be answered, but I imagine we’ll get at least one.