Yes I'd be a fourth and I think that my friend Doviculous might join as well (he was with me in the Disciple's of Vader. I'll touch base and ask). I think the Disciples of Vader can coexist and be absorbed in the Imperial Remnant as a sort of splinter group of the Imperial Knights. They would hunt to kill the extremes of the Force Spectrum (i.e. full Dark, full light) and hunt to capture and absorb unaligned, untrained force users. Perhaps there can be one umbrella school within the Remnant that allows the students to train in a broad spectrum and then decide on their own which path to take (Vader lackey, or Imperial lackey). I'm thinking that be fairly independent of the Empire as the Jedi were to the Republic oh so long ago. They'd be serving the Force side of the Imperial Knight philosophy, while the Knights serving their Emperor. Sound cool?
(WARNING: DISCIPLES OF VADER WERE ORIGINALLY INTENDED TO BE DARK SIDED.)