Absolutely loving the toybox! I would list off the positives, but then I'd be going on for WAY too long, so assume everything I don't mention here was done well!
In terms of the special camera angles, I guite liked the 45 degree camera angle, as it is more unique than the standard bird's eye view camera. Although the latter of which would make solving certain puzzles easier, I feel like the former could be used to cleverly hide some quills (as long as they aren't frustratingly placed!), so basically I think both cameras are great and both should be used when appropriate!
Now as for issues I have, there's nothing too major. First off is the swimming. I feel as though you swim a tad bit slowly - maybe make it so that you can hold the trigger to speed up (for a bit of strategy make it so that you can't ascend or descend whilst sped up - but that's just idea!)
Also, I'm sure you have probably noticed and addressed this, but I feel like there should be some special animation for when you are about to roll, but aren't moving. It's rather odd to see Yooka and Laylee just frozen when you are at a standstill, but then again that's probably because this is a pre alpha!
Another nitpick I can think of is to do wit pushing objects. Ilike how the physics allow for rolling balls and pushing crates, but I feel like some pushing animation would help it feel more satisfying. Maybe make it so that you have to push it by holding a button down, therefore allowing you to pull it as well!
One feature I would like to be implemented is a first person camera mode - as it would make climbing to the top of a mountain and looking around much more fufilling, and it will help with trying to discover where that secret button is!
If this toybox is anything to go bye, then this game will be surpassing my expectations! Excellent work!
TL;DR: I prefer the 45 degree camera, as it can be used to sneakily hide quills, but both cameras should be used.
I think swimming should be a little faster of there should be a button to speed swimming up.
I feel that maybe a button to push and pull objects would be better than walking into objects.
And I also think that there should be an animation when Yooka and Laylee are in the rolling position but aren't moving.
Finally, a first person camera mode would be a great addition.