Luckily, someone has already done a lot of edits to mutiplayer maps to enhance the PVE experience, You can find them by searching teamplay ai or teamplay_ai on the map vault.

@IDontKnow Thanks mate. I'll keep my eyes open for a sale. Son needs to learn resource management which I think is simpler and more "obvious" in StarCraft, which is free to play. I'll install FAF for myself in the meantime!