Ah, see using brushless seems like a good option to me - the ESC side of things looks like it will be a steep learning curve - if it's alright with you, I'll reach out when we're about to wire up to ask hundreds of ESC tuning questions! One of my friends uses Rotomax 100cc ones in his helicopter (does all the crazy stunts in it), I'll ask him as well.

I wonder if some of the smaller brushless motors could work as drive motors?