One of your maneuvers could be riposte (which gives you your counter) plus 3 others (Grappling strike, Trip attack, Disarming strike look good).
Your enemy attacks you and misses, you Riposte, punch them in the face and Stun them (negating all further attacks). It's then your turn (and they're stunned) so you then kick the crap out of them (with advantage) using Action surge, and maybe using another die on Disarming attack (they automatically fail the save thanks to being Stunned) as you do so, plus a flurry (which if you're OHM also automatically knocks them prone) or bonus action MA attack, and maybe stunning them again.
If you're an unarmed monk you can take unarmed F/S for d8 damage punches, and then when your M/A dice catches up, swap it out for an extra manouver and extra dice via the Superior Technique F/S.
I wouldnt want to fight that guy one on one.