From what I saw, that's within the realm of possibility, Spazzy. Want a system only to be visited by small ships? Make a cavern with a jump hole in it. Want a system only to be visited by capitals? Make a system with intense radiation. Want ultra-rare ultra-buffed NPCs that spawn only in certain areas with are rare chance? That's doable, even with a server that stops producing NPCs when more than 50 players are online. Have them drop rare stuff? Doable.
Have people not finding exploits: Never possible.
To be fair, I'd rather not have them drop ultra-rare stuff, but rather stuff that has the value similar to battleship remains. Those things are actually pretty well regulated with the things as they are right now. Everything else, really, should only be event-stuff, and even in events it's hard to regulate who get's the stuff. As someone who planned and did events in other games, administrative, I pretty much know what you mean, Spazzy, especially the frustration when you see people always finding loopholes or just be greedy, like people piling on a station to get rare stuff or people using cruise-snubs to distract NPCs.