There were a few mistakes here and there, but the main thing is you lost your com early to scorchers. Everything after that was kinda just deciding how you lose, not whether you lose.

Coms now lose you storage, on top of their MBP, 4 metal, and 6 energy. Losing one before mid-game is 99% fatal in small teams.

But there is an easy way to address this difficulty. Get either a machine gun or riot cannon on your com. Now that coms have +800hp, they're almost impossible to lose if you're prepared. For the cost of 50 metal you would have killed those scorchers with no further cost, and then likely won the game 10 minutes later due to the enormous territory lead their lack of army would have given you.

Outside of losing your com frivolously, I think you played fairly well.