Since I'm beginning to feel like there are beginning to be too many buttons/options anyway; I'd rather go with just keeping restart/replay as it currently is [auto replay] Like I said, my main issue was with backtracking and save state. When it comes down to it; I think having two hotkeys for replay and restart wouldn't be much different from the current system of press a button, replay, press once more to cancel the replay but the current system is simpler.
So yeah, my vote is for "change it so R is exempt from the auto-cancel"
This, while I might have been a tad annoyed by it at times, at least feels expected to me, while the backtracking/save state thing did not at all. This is the simplest solution anyway, I think.
I'd rather go with the "restart and clear replay" hotkey. I always press the replay hotkey when I restart my levels and for me find it convenient when the level is replayed.
If you mainly like replaying, I'll assume you're not annoyed by any of these issues then I'd assume
not having more buttons would be better. And to be clear; if this option is not checked the game plays exactly as it did before for everyone else?
EDIT: I also just noticed that you enabled auto-replay when you retry from exiting the level to the end screen, awesome! thanks