cooldown resets

[BillyKaplan]

with the game being balanced to that effect.

Balance? The skills you mentioned are only as powerful because they're on such long cooldowns. If you want a shorter cooldown Benediction, it's called Tetragramaton. Notice the weaker potency to accommodate the shorter cooldown.
Also, so many people claim the game is too easy as-is, I wonder what the game'll be like if you can pop Bene and Hallowed Ground on every pull. Also, I get the feeling it's a bit exploitable. Tank pop Hallowed Ground, then lets themselves die. Death resets their agro so after they're raised, they enter combat again and Hallowed Ground is up again. Ultimatum + Circle of Scorn and all the healer has to do is cast their raise. That's not something the devs would allow and is only one example out of numerous many I'm sure exist.

Reset on instance-entry doesn't hinder anything. If you can disband and re-enter to force the cooldowns to reset, you're not affecting anyone else and only making your own party's life easier without the actual content needing any changes.