[Edi]

To echo Ironhawk, it would be a massive workload and then some to rewrite everything from scratch to support classic turns as well as simultaneous turns.

I love the simultaneous turns aspect of Dom3. For a game that uses both simultaneous and turn-based systems, take a look at the Age of Wonders series. In that game, the simultaneous turn structure is far more like RTS, where the quickest click gets the prize more often than not. I hated that, always played it in classic turn-based mode. With Dominions, even if the option were there, I would not, because Dom3 has true simultaneity.