Of the main Autobot cast, Grimlock is the one that the best handled, but that's not really saying much. He's the focus of one of the best Season 1 episodes (the one where the other Dinobot shows up) and honestly has the most intrigue surrounding him. He was a Decepticon how exactly? His record states he accidentally destroyed some stuff, but seems too young to have fought in the great war. So does the Cybertronian Counsel just label all criminals Decepticons? Is that how they get away with carting them off on a prison ship? This has been an interesting plot point since Day 1 that they have barely addressed. I think the last few episodes of Season 3 are going to address this (but Wikipedia has been wrong before, as I remember looking up stuff for Animated back in the day and seeing stuff on Wikipedia saying that Barricade and Blackout were going to show up on Earth in Season 3, specifically), so hopefully it's satisfying.
But this is a huge problem with the character. Despite the intrigue, that's pretty much literally all he is. He's had a few interesting episodes dedicated to him being a giant green T-Rex on Earth, but, again, like all the other characters, he hasn't grown any. He's still basically the exact same Dinobot that yelled "Did someone say punching?!" with half his head stuck out of a stasis cell in Episode 1.
It's like I always say: always consider the Cybertron games to be completely separate from the TV shows. They don't line up at all.
Also, the writers on the show have stated he's a different Grimlock and that "Grimlock" is just a common Dinobot name.
Another area that RiD fails in is something that Transformers has never really dealt with before. Granted, what I'm about to go through may be too dark for a more kids-oriented show, but since RiD is a continuation of Prime it should have shown up at some point.
How long has it been since Prime? It doesn't seem like it's been that long, but that may just be the style and it's been a long time (the former military base looks like it's been abandoned for a decade at least). So what about the human characters from Prime? If this isn't too long after, wouldn't Bee want to go see Raf? Is Raf alive? What about Jack and Miko? Would he like to visit with them, too? If it has been a long time, have they all grown old and died? For giant alien robots with lifespans FAR longer than humans, what's it like to lose a human companion and still be there long after they're gone? Sure, they got to say goodbye at the end of Prime, but they didn't think they'd be coming back to Earth (even though it was a quick space-bridge away since Ratchet got to Cybertron from there easy enough and Bee later on). Wouldn't actually being back make Bee want to see his old friend if it wasn't that long after? Raf was some sort of tech genius, what if he started a tech company and just so happened to be located in Crown City? Could Jack and Miko be the new government liaisons, checking in now and then?
For all the faults Energon has, at least it included the old cast from Armada to some extent. RiD doesn't even have to go dark with the "how do I feel that this person I knew as a kid died a long time ago?" thing. The creative team had some interesting material there on a silver platter with a grown up Raf, and has done next to nothing with it. I wouldn't be that bothered by it, except the majority of stuff in the show is just rehashed 'lesson of the week' stuff we've seen time and time again. You know you're running low on ideas when you do a brain-switch episode.