Its using HL gearboxes, so not so many options on gearing - I did try picking up "faster" motors before I left the US, but they draw way too much current for anything I can drive them with (the specific ESC for them is rated at 69A apparently!)
Original Tamiya DMD 'racing' gearboxes are like hens teeth as well

I did think of Lithium based batteries as they can support much higher current draws?

In Europe we are really starved for decent brushed motors, so option C would be to hang out for Brushless compatible battle boards...