1. A rolling sound could be the sound of rocks cracking underneath or sands shoving out of the way. You don't have to be an "expert sound designer" to try (as students they also have teachers to ask for help). I didn't say this because I cannot see when I am rolling or not, I said it because it breaks immersion when you cannot hear the character interacting with the environment even though it is obvious there would be sound from what you see on the screen.
2. Not being able to jump in roll mode is an issue. Not sure if with "slightly in the air" you mean that the character came off the ground even though the surface looked flat and not pressing the spacebar, which is also an issue.
4. They've removed the scaled boostpads I was talking a while ago. Did you play an old version?
5. We'll see ;)