I can't really comment concretely on the legalities of these servers, other than to say that it is my good faith belief that any compatible server developed from reverse engineering efforts that does not use the City of Heroes intellectual property (art assets, names, places, etc.) would be legal.
Except, unfortunately, it would no longer be
City of Heroes.
If NCSoft is going to send a cease and desist, they'll do it regardless of these token measures. And the existence of these measures are already a signal that the team working on the server can be bullied. It does nothing to the cards in NCSoft's hand, and these preemptive concessions are like blood in the water.
I'm not saying the community server is a bad idea. I think it's a great and wonderful idea. The dev team ought to be willing to see the game go live again, even if that means dissemination of the code, and they ought to be politely clear about that for any corporate lawyers who are listening. You can't know how a publisher will behave; but you can know how you'll behave, and let it hang in the wind for anyone to see.
But stripping it of everything that characterizes the
City of Heroes universe and back story will be another painful reminder for fans of the world that they've lost; and to add insult to injury in the worst case scenario, it would offer no legal protection anyway. The Freedom Phalanx, Wyvern, Longbow, Freakshow, the Fifth Column, the Menders, the Midnighters, Lord Recluse, the Praetorian War, the Coming Storm, Paragon City, the Rogue Isles, all of it will still be vanished and unresolved forever.
I am a fan of the world and universe and continuity that Paragon Studios built, not just of the great costume creator and collections of stats and game mechanics.