I am not quite 50, and haven't (obviously) participated in any raids, although I played WoW for a couple years and finished multiple expansions, so at least I understand how raids operate. I had this idea for a raid similar to Kefka's Tower in FFVI. Now, for those that are fans of this game, you'll immediately grasp what i'm talking about.
In Kefka's Tower at the end of the game, you had to choose 3 parties of four, drop off your airship and go through separate paths (and the parties had to help each other through by hitting switches other groups couldn't get to). With the way it sounds like a 24 man raid works (with 3 groups of 8) I automatically thought about how cool it would be to see a raid like this. You set up your three groups, "drop in" and coordinate together to make it through the initial part of the raids separately. You have three "separate" bosses that are all linked together to where they have to die together (within so many seconds/minutes/etc.).