Concerning the raids: just to get some rust out we ran all of them, consecutively, in one evening. Just a hair over three hours, on hard mode, doing the challenges in Kings fall and WotM. The one we had the most fun with, and are looking forward to the most is the vault of glass. As to ongoing support, my guess is well get one, maybe two years of continued play before they start shutting down the servers for it. May even be sooner if people don't populate destiny often enough.