you should add haste,crit,mastery and other secondary stats :D,then the armor and weapons would be a little bit different and not only strength,intellect,agility.
you can fly with the boost by pressing it pretty fast but not holding it down. you get a small boost in the direction you're heading.It's much cheaper to just press boost every now and then in racing.
Strange,i crashed a atleast 100 times bigger planet than the sun at the sun and then it just got destroyed and vanished and nothing happened to the sun... :/
the ability to temporarily fly with the boost kick is actually a bug but we're leaving it in for now because its fun to play with : )