Good Job
First off, I'd say that any changes you make from now on are just improvements, it's great as is and it's lots of fun. One thing that would be pretty cool to add tho is some sort of ball. so that you can drop it and have it bounce off of springs and maybe add in boards on an angle so it can bounce or roll off of them...i dunno. I don't have a clue how much work it would take to make something of that sort, but I think it would be pretty cool. Anyways, great job, keep up the good work.