that's a great point about opportunity cost. what it makes me wanna do instead is add to assess a one-turn "stun" flavored as the enemy sizing you up in return. a little bit of calm before the storm.... of course you could have enemies size you up regardless, but there's a neat unexpected flavor if it's something they always (or *usually*) do in "response".
the idea of different enemies coming with different limited sets of variants makes me excited all over again about transplanting these mechanics to a dungeon crawling setting.. i think it could really work for like a 2-4 hour single character rpg. i've always liked it when rpgs emphasize "learning" enemies, and getting to pick up like "ok these guys never actually excel at speed, so if i'm getting outsped it's ALWAYS a me thing" is a very texture for that. you could also use different language for different enemies adding a layer of interpretation when dealing with new foes - a high attack griffin probably doesn't have "sublime grip" but maybe a "hooked beak" or even something more abstract like a "predatory gaze"...