Transformers Prime' ended with a pretty satisfying wrap-up, but fans like me who craved more got 'Transformers: Robots in Disguise' (2015) as a sort of spiritual successor. It's set in the same Aligned Continuity, though the tone shifts to something lighter—more comedy-focused, with Bumblebee leading a new team. It references Prime's events, like Megatron's fate and the aftermath of the war, but it doesn't feel like a direct sequel. There's also the 'Predacons Rising' movie, which ties up loose ends from Prime's finale, showing Optimus's sacrifice and the rise of new threats.
Personally, I missed Prime's darker storytelling, but 'Robots in Disguise' has its charm. If you're into lore, it's worth watching, though don't expect the same emotional depth. The 'War for Cybertron' trilogy on Netflix later expanded the universe, but it's a separate continuity. Prime's legacy lives on in fan discussions, though—I still rewatch that final arc with Unicron for the sheer epicness.