I agree! It's a great concept but needs some aesthetic tweaks!
You could fix the "high suspension" (XD) problem by making the car mode bigger, so it'll have to be your own mold, likely. (Or put a kid in this size mold)
Then you can stretch out more and therefore get closer to then ground. But then you'd need a skateboard on your stomach too in addition to your lower legs...hmm. I guess you won't as long as you work out the right muscles!

That's an awesome idea for "working" transformable stuff though. It's already giving me ideas for other designs...
edit: Fixed a typo