Thanks for your advice everyone. I will look around at the different teams, although I’m pretty confident I will end up joining the rocket team, and then consider starting my own the following year or the year after that, when I have more experience with how teams are set up, etc.
I might even choose to just run for a leadership position at the Rocket team instead of starting my own (design teams at my school are run by a ‘government’ where people need to be voted in).