Four Vehicles

For my next year studies I'm going to try to get into the Art Academy in Oslo. There are several classes and I'm gonna go for the Visual Communication study which is mostly about computer graphics and suchlike. To get in you still need to do some tasks though to show your abilities. The first task was to draw a vehicle, so here's some early simple concepts. I'm not quite sure which one I should go with. Feedback is very much appreaciated.

No offence, but the airplane and the ferry looks very flat, with no sense of perspective at all. The other two looks fine from that point of view, but the bike is really weird imo. I can't really understand the shape. Perhaps you could try with something more realistic?

http://www.wc3campaigns.com/gallery/...cat=500&page=1

meh.