(Wanted to give this a more in-depth response that my initial reply.)
Thank you for giving my game a read and I see where you're coming from now. I see the level of depth you're looking for in a simulation of 2D fighting combat, it's a little too focused in scope for my design goals here. As mentioned before, I aim to approximate, not simulate. I want my games to be strategic but quick; simple, but deep. What you describe is far more in-depth round to round than I'm looking for. Further, such a system I feel would be too focused on one-v-one combat. While that sort of combat will be present in FoF, the game is more designed around a fighting game/wuxia setting. Adventuring across the globe, and regularly group/team combat will be just as prominent parts of the system. Something as in-depth as yo simulate split second footsies decisions would slow group combat significantly.
To address the movement in the system as is, you bring up the Grappler v Zoner example with them both at 1 MR. You are correct. In that situation, the Grappler would be very hard pressed Twin that fight unless he could come up with something clever to even the playing field; however, this example excludes the asynchronicity and openness of character creation/advancement. Not all fighters will be on even playing fields. Players are not bound to a single archetype as they construct a custom fighting styles. In this example. That Grappler might have also taken levels in the Zoner or Juggernaut archetypes, either of which have longer ranges, which the fighter could switch to during combat. Or if they didn't, and they loss, that same player could spend their experience points to pick up a level in a ranged archetype, or learn a technique to improve their movement or a ranged attack.
Please do not misunderstand. Even though I feel like my current design goals clash with other fighting systems you enjoy, I am still very grateful for your feedback. I was already in the process of tweaking the combat system to better approximate that chess at 100 miles an hour you're looking for. I will definitely check out Heaven/Hell and see what inspiration I can take from it, but fundamentally Festival of Fighters was not being designed to be a game like that. I understand that with your preference against turned based systems that the final system may not be to your taste. I hope that the book can still make for a fun read for you in the end in that case.
Regardless, thank you very much for the comment and the enlightening conversation.