The Vista Viewer
Have already suggested that countels of times by adding it as a Theatre Mode as a kind of Account feature being unlocked via getting achievement points to a specific point.
Such a gameplay mode (usable from Character Selection) could be used then also for example reviewing a Characters personal Story as a kind of Mini Video that retells your characters full complete story in regard of all your decisions and this including all of the (accountbound) living story parts your characters have participated together with maybe an option to turn that Video into a Youtube Link so that you could show others your character’s “legend” ^^
Personally I like the idea behind sub classes ~ quoted from Chris Whiteside