Not much opportunity to do enough good tricks on such a short course. You should be able to build up turbo while in air, just not as much as doing a trick, which seems to be either a wheelie (if at all), or a full spin. When you fall towards the ground from a high jump, the ground isn't visible and it's hard to tell when it's coming... scaling would be helpful here.
Game definitely needs some tweaks and a bit more speed/acceleration