With any 'analysis paralysis' build-your-own system, I suggest what we did with Elements of Magic. You get a set of signature moves that you've practiced, which you can change if you spend {{insert time here}}. Those you can do as a normal action. If you want anything not on that list, add on an extra cost. For spells, we made it take two rounds to cast, so you'd almost never bother in combat.
For a fighting maneuver, I'd say using a non-signature move would require one round to look for the right opening, and then you could use the maneuver the next round. Basically, you can say on your turn, "I'm looking for an opening," and you have a few seconds at the start of your next turn to decide on what move to use. If you couldn't figure out what to do in the intervening time between turns, you either need to use a signature move, or wait another turn. (Which is almost certainly a bad idea.)
