Held action would be interesting but I think, for what Swen said in a few interviews already, trying to get your characters in the same initiative circle by killing enemies in between, as a puzzle of some sort, so you can swap them as much as you like is what they are aiming for. And so if you could delay your turn, it would make it too easy maybe?
it costs you a reaction to do it. So you are essentially giving up a lot of options every time you do it. You only ever ready an action when you dont have a better option but you know there will be an option before your next turn. Usually this is because theres no target in range, but you know they will be moving toward you
I think Ready action would vastly improve the "1 action per turn" system. Its jsut a matter of implementing it in a manner that will not be ridiculously convoluted. Bumping yourself down in the queue may in fact be more complicated to implement than a proximity targeting command(Overwatch). Either way the goal is to provide a dynamic action, it will work with every spell/ability in the game and will improves options for your turn. I think the limitations would pop up if they try and make sure that the AI has the option to do this as well. Thats where problems for readied actions would start to flourish
