I can get on board with that.
As I read it, 2 things become very obvious to me though:
A TBS system will have to strike some sort of balance between complexity/depth and it’s ability to be picked up and executed by casuals.
If the system is too nuanced and complex it will turn off the casuals who don’t know grappling.
So my suggestions to the devs if they read this:
A TBS can be made easy to pick up and play while also allowing for a “tough to master” element. But it needs to come with a deep tutorial mode. You have to show the steps and animations of every sub so that someone can watch and even practice what a start-to-finish choke looks like example.
It should also have some visual & audio queues in-game about what is happening with options to turn off queues.
Example:
Attacker transitions to stage 1 of armbar from bottom guard.
Animation: Bottom attacker grabs wrist control in a slightly exaggerated way.
Visual queue: The animation itself of course. But also could pop up a small graphic at the top of the screen showing 1 of 3-5 blocks filled in. The total blocks represent the # of stages needed and can vary based on the sub. More complex subs should have more stages ie. Armbar versus gogoplata.
Audio Queue: SMART COMMENTARY. Rogan or Anik should say “He’s got wrist control he’s going for a submission here.” As the stages progress to the end stages commentary can say “he’s nearly got it locked up”
Things like this go a long way to help casuals know what’s happening. And options like this can be turned off.
You could even incorporate “Hints” for defending in offline modes to assist the learning curve.

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