Hm, yeah I suppose with the indication, the player has a large enough window to parry while largely ignoring the guard on other instances. I guess I'd be satisfied if parrying on it's own was a little bit more of an independent action. Like I said before, I just want it too feel too scripted or too much like a QTE, so I think I'd be satisfied if they just made the window for pressing square a little shorter, removed the button prompto, and made the animation/slowdown less exaggerated so it flowed better with the rest of the combat. Ideally though, they'd just make it so that L1+Square has noctis put his sword up independently of what's going on and you just have to do it in time with the indicator/attack to parry, so that it essentially exists as it's own thing.
