So here we go.
This is one I've wanted for a while. With flexible raiding now a reality, I'm drawn back to the idea of being able to scale your level down to run older content with friends, something the late, lamented City of Heroes had (called mentoring/sidekicking in that game). We've been teased with this potentially existing as recently as October of 2013 and whether or not it was a hoax then (I personally have no idea) it's something I've wanted for years. Sure, it's fun to bring your level 90 to an old dungeon and blow it up sometimes, but I want the option to step myself down and run it at an appropriate level in appropriate gear if I so choose. I'd also like to be able to boost a friend up to my level so that we can run stuff together, although I suspect the free level 90 boost is aimed at handling this same problem. Basically, anything that lets friends do more stuff together, I'm down for.
And speaking of that...