it's simple and how it should be imo:
Nwz - only solo. No grouping. Here you learn the basics, your class and get your first gear.
Rwz - 4-man, 8-man groups. No solo(big no here for undergeared/pve people). This wz enter only people who seek greater challenge.
Right now, Level 50 PVP is grossly unbalanced and PUGs are getting steamrolled over and over again by the WH premades. It's not fun for casual players and ultimately self-defeating for all involved, including EA/BW.