Well, TNA really doesn't need nor have a place for Christian anymore, so it would be wise to just let him go. As for those four superstars mentioned above...
Kenny Dykstra-I think I speak for most here when I say that WWE really killed him beyond repair. I mean just his ring name alone was pretty gay. His image wasn't that great. He has an annoying voice and he attempted to get over as a cheer leader, a male cheer leader. I think TNA isn't stupid enough to sign this guy.
Elijah Burke-Yes. I see this guy filling the mold of a Booker T, no, not just because he is black. He has a good build and is very athletic. He has fantastic mic skills, but just needs to restart his career since he has been out of action for a long time. Hopefully he can find his way into TNA, this should be TNA's number one signing in the near future.
Paul London-If I am not mistaking, I think Paul London was in an Ultimate X before, so yes, he is welcome back in TNA anyday, he is a great X Division style wrestled when given the chance.
Lance Cade-His tag team run killed him too. Let alone his lack luster apprenticeship to Jericho, he is pretty lame all around. Has no real personality, pretty boring, sure he is big, but so is Matt Morgan. As a matter of fact, Matt Morgan could devour Cade in one bite.