I've played this a few times before, so I'll try to focus on whats new.
The gems for comsetics fit I think, but the white tophead is stupid and you know it.
You have faster tilting once your a bit through a loop, so you can easily complete it. This clashes pretty hard with the precise movement you require with the rockets in order to get through the hoops to get your Energy back. Pair that with the already really wonky air movement thanks to it being momentum based ( which isn't wrong obviously) and the vampire Race (or every rocket required section basically) became a huge chore, and not very fun for me at least.
It would also really help in the vampire race i.e. if you could actually see a bit further or something to know where you had to go. I often managed to barely make one of the floaty turns only to be completely unprepared for the next, which needs to be prepared quite early in advance to make it.
I was surprised you had voice acting for Poo, but I guess you had voiceacting for the normal bear before aswell, I just didn't really register it as such, since its just roars.