The Monk Temple

[Allyrion]

That's not too low for T5 or T6. Only need 458 for T5 (except for the brief time during which you're forced to attack Asclepius from the front while dodging divebombs) , and I haven't missed a single hit on Rafflesia in T6 with 469 accuracy (which I'm p.sure is above cap for t6 as well lol)

I missed like 4-5 auto attacks at 469 accuracy is T6. That's in the acceptable range to me, but it's not the hard cap.
At that level, you'll only probably miss some auto attacks once in a blue moon so I'd say anything between 466-475 is the best range.