I've seen MMOs implement a revive system where if you use the "revive skill" within 10 seconds of a player dying you can save them from death. It really makes large scale pugging bearable. It creates a challenge for the players that really know what they're doing when they have to go save someone, and it helps the players who need a crutch.The only issue with the system is that it tries to go for 25 man (excluding balance). While it solves lots of DPS queue problems, it creates TONS of more due to the nature of PuG groups that has been evident since Wrath. They should've sticked with 10-man.
It's something I'd like to see implemented in the LFR system.
After all the LFR system should be for players that just want to turn on WoW join a raid and quit in an hour or so. LFR should be a mindless hack and slash with very little thought put to strategic gameplay. Damage should be dealt out but easily healed. Tanking should be glorified DPSing. And DPSing should literally be, "does it have a red bar above it's head, kill it." Stay out of fire mechanics are welcome in the LFR system, but they should be very forgiving hopefully. I would expect to be able to stand in fire for a good 6 seconds before dying, and my screen should flash red. It would really pay homage to the way games are currently geared towards casual play. Think about the last single player game you played, where you didn't have ample time to get out of bad stuff when your screen flashed red? Why can't WoW give casuals this in a raid. I think LFR can deliver this and I hope it will.