Thanks for playing! I love seeing different takes from the same concept.
I agree that polishing is more important. We dedicated only two days for implementing mechanics. Anything that don't make it by then are cut out. The last two days were just playtesting and polishing, there were so many issues that we wouldn't have solved otherwise. There's a lot of interesting design problems and it was cool seeing how others tackled them.
We did plan and try out a few other mechanics, and of course with other vehicles. They ended up not promising enough for us to include, so we just improved what we had. But now that the jam is over, we're already in the process of adding a new vehicle along with new mechanics :)