[Taqwus]

The time to win battles is, not infrequently, before they start. This is particularly true given the variety in Dominions, where many tactics can't be countered with mere battlefield manuevering but need decent preparation beforehand.

In any event, human-controlled tactical battles don't mix very well with PBEM, even if you limit control to pretenders. It would also alter balance; there's quite a bit of magic that would be considerably more powerful if the user had fully controlled target selection.