Well, they updated these in yesterday:

This backer room gave me a buff that made stamina/energy restore immediately for a brief period.

I've seen one that does a chain lighting like effect. as well as one that ups your armor a lot. and one that is "refreshing" still haven't figured out what that one does yet. I assume it heals you or refills your health potions. but i haven't run accross it when I'm not full on health yet.

Refreshing does a full heal as you said, though wasn't paying attention to health pots when I picked it up. All the buffs I came across are:

Insane energy regen (As mentioned in first post. Was able to corrupted dash all the way up the cathedral elevator to the east lock without having to race against the gas) Armor increase Chain attack Health restore Triple bullets when firing gun Reveal all corrupted treasure Speed increase Damage Over Time Corpse Explosion

That's what I remember off the top of my head.

I would love to see an RNG manipulation at some point to guarantee a Energy Regen Buff. If this game ever reaches an optimized state it seems to me that the WR would belong to whoever gets the best placed energy regen buff in Region 3