Hmm....well you should be aware that, generally speaking, wraith units are bad in CC. The lord and knight will be ok, but the others are vulnerable to being tied up in CC. They get too few attacks, so once they're in CC, they'll probably stay tied up for a long time if they don't die.
I mention this because against skitarii, I know you may end up being assaulted by things that can kill your wraithguard(the wall of death rule helps, but can be avoided by sacrificing a cheap unit).
But either way, let us know how they do once you get them all assembled and on the tabletop! Maybe they'll surprise me! Battle focus is certainly nice, though it'd be better if they were in the craftworld warhost, where they automatically ran 6". But that MIGHT make them quick enough to make the list work well, with a bit of luck on run rolls.