Hear me out: One of the greatest aspects of playing HC is the tense feeling you get fighting a boss with a buddy and knowing there's a chance you get wiped and lose it all. The problem is the game in its current state doesn't seem to give you any way to interact with your teammate in a way that enables you to rescue one another.
Imagine fighting The Count with a friend, and your buddy gets hit with one of his sweeping attacks, misses a flash, then gets frozen by an ice blast into stun lock and death. Normally your friend would just have angrily watch as you fight with a slim chance to come out on top with half the DPS, but there's still that hope that if you beat him you can revive your buddy. I know there are purists out there who think this is sacrilege, but I think this is simply optimizing for fun. When there's still a chance the tension is that much more intense, because now the stakes are so much higher. The interactions you'll have will make a full wipe so much more demoralizing, and the victories will be that much sweeter. More importantly it'll be a heck of a lot more memorable either way.
Quite frankly, I'm not sure why you would have a revive option in Standard over Hardcore, since it's but a minor inconvenience to have to do the walk of shame back to your fallen corpse for the former, and a completely dynamic changing feature in the latter.
I realize there are things like pausing the game or ALT F4'ing out, these would have to be fixed first, and it would need to be an option you opt into when choosing HC, but I can't see why this simply wouldn't just make the game that much more fun with a friend or two.
What are your thoughts?