I use thermite VTOLs at the end too. I don't build any fighting units - just 13 trucks.
I take the middle derricks, protect with machinegun towers, build two machinegun towers on the ramp of the bottom middle base and rush a truck through the base to build two machinegun towers to take the base derricks. I research straight for VTOLs and superhot flamer gel. Once allies have researched lancers, I build lancer hardpoints to hold the middle and protect my derricks and allied bases.
This give me enough money to keep up full research, build 4 VTOL factories and a bunch of rearming pads in the middle of the map. Then once thermite has been researched, I have 4000+ in the bank to start pumping out thermite VTOLs which I use to take out all enemy production facilities and mobile units, which wins the game in under 20 minutes every time.
If allies choose flamer research early on, the game takes 17-18 minutes. I vary the speed throughout the game so that no time is taken up with me clicking - all the time taken is just doing the research and using the VTOLs.
Enemy don't build AA until attacked by VTOLs, so if you look after your trucks, you don't have to lose a single structure or unit.