Here's a new grappling control idea (expanding, still on the ps controller -sorry X Box-ers):
Use L2 and R2 as "grapple" buttons.
L2 could be for the hands, and R2 could be for the feet.
Let's say you have your back on the floor, with your opponent in the guard position. He starts to rain punches on you and your leaning, dodging and blocking is still allowing a few punches through and lowering your stamina, so you decide to clinch (hug) your opponent to catch a breath from the damage you are taking. You can press L2 (our "grapple" button), then the buttons that corresponds to your character's left and right hands to hug. You may even need to press UP on the R stick (remember, that it is for sitting up) to reach your opponent if he is leaning away from your body.
You can stay hugging as long as you are holding the L2 button, unless your opponent starts mashing a button such as the left hand button to push you away with his forearm to your neck/face/ or throat. To remain "clinched" with him, you should have to mash the same button your opponent is, but faster to over-power him and maintain your position (while still holding L2).
When in this position, your can open or close your guard by pressing R2 (pressed=closed, un-pressed=open).
Say you are in the guard with your opponent, and you want to try an armbar from this position. You are holding R2 so he is in a closed guard. You hold down L2 (the "grapple" button) and press UP+LEFT (diagonal left) on D-pad to indicate opponents screen relative right arm is your grapple target, then your left hand button. This puts you in a closed guard with you holding opponents right arm. Next, you let go of R2 (open guard), tilt controller to the right to shift your weight to your right hip (which attempts to swings your left leg in front of your opponent's face), then hold down again R2 to lock your feet together at ankles. Your opponent can mash his right arm button to prevent you from straightening his arm out, or he may hold his L2 button and hand buttons to grab his own hands to prevent you from finishing the armbar. You both may get into a button mashing frenzy at this point: you to try to get him to tap, and him to try not to get submitted. Since he is in the more unfortunate position, he has to mash the button faster, or he might be able to lift you up by shifting his weight back (leaning back) then forward (leaning forward) to attempt to slam you.