@Lithium
Well, you can softcode out turns in the 'order of operations' kind of thing; I've done it before. Just make the commands to do stuff advance the turn if it's something that would do so.
You could do mechs by having statted objects with controls though that can be unwieldy; it's what we used for Exosuits and mechanical armor and stuff at Transformers and Megaman games. Something like a 'mode change,' where the mech stats are stored and switched to the main stats grabbed by the combat system when piloting, is easy to do.