Having a system in place that allowed players to queue to explore and fight different ever increasing difficultly bosses would be great. Looking at something like Diablo III's rift system, could be pretty cool, and the longer you last, the better loot you get.

I'd just love it to be something along the lines of 4/8 man content.

Random could be fun, always changing, but there might be a group of people who would avoid it because it's not the most effective. Anyway, I'm always down for more content.

Imagine running a dungeon to find a version of Titan, I think if they did something like that, they could update the content to the current level cap, and give them a reason to update older content and bosses. I just wouldn't know what the lore behind it would be.