I don't know. I mean, given the strengths of the other backs, I'd probably go with Long as he's a very good 1v1 defender and that isn't as much of a strength of the others. Both did very well in this past camp.
CCV has been in great form, by all reports and stats, for a good Swansea team. Swansea is probably the second best club any of our CBs are currently playing for. I wouldn't discount him so much. He is also much younger than everyone you listed. Long is great at certain things, but not particularly good at making forward passes. For NYRB, it is mostly Parker that tries to do that and Long mostly passes it sideways to him. I bet that is something Long tries to add to his game this year, but we will see. I'd put Parker even with ZImmerman and both behind Brooks, Miazga, CCV, and Long.