I don't think Vaders have been too annoying in the last several months, at least in my area. There are usually only a couple, if any, whenever I'm checking the pegs.
If Hasbro does plan on keeping a Vader in every case until 2018, I would want to see an updated Evolutions Vader with the new hip and wrist articulation. If they were to make that one 'ultimate' Vader and keep re-releasing it again and again with an interesting new accessory every time (ROTS-esque 'environment' display base, crate, railing, mouse droid, doesn't have to be too much) then I'd be fine with that.