Playing against the AI

So, I'm having trouble beating the AI: I can manage up to 2 hard opponents, but when I'm against 3 on a large map i crumble. I believe i lose some tempo between classical and heroic as i can't decide between booming with the beaten AI's town centers or continuing the aggression to finish off the second. Can someone have a look at the recording and offer advice? This is against AOModAI link : [https://ufile.io/lfqoo] (alternative [https://1fichier.com/?ohq99elf6h])