I'd be up for a bit of this.
First choice would be a TRX-3 but no idea on release date and which class. If not then I'm sure my Top-Cat/Cougar hybrid would be old enough.
Would have to run on Lipos as don't have any other cells. I would prefer unrestricted motors as want to run brushless without buying a spec motor just for this.
If going down the controlled motor route then don't make them too slow! Make it a race, not a shelf queen parade!