It's interesting that only Fake Velo is left as the only unconfirmed character that was previously playable. I can only assume they're planning on a CNK themed season later down the line post-Spyro season, probably with CNK adventure inspired challenges and a unlockable Fake Velo and the iconic hoverbike looking boss kart they used in CNK. Can't imagine what kind of track that would come with though since we already got all of CNK's tracks, perhaps a new track that invokes the hub areas from CNK?
Gotta say that the fact that the Back N. Time Grand Prix is including baby versions of Crash and Coco but not the iconic baby versions of Cortex and N. Trophy is kinda upsetting me. Just look at them.
Given that the first GP will include 5 characters (Tawna and the 4 trophy girls) it's not out of question that in addition to baby Crash an baby Coco we might get Cortex and N. Tropy babbies too.