Lottery spawns are all well and good but they are heavily designed around place holders and there is nothing more infuriating than killing loads of place holders and some random coming up and claiming the NM you just spent 1-2 hours trying to get to spawn.

I think 20-30 spawn sites which are varied enough to encourage exploration is the best way to go, this way they could also stop any bottleneck area's or roadside spawns from ganking low ranking players.

Another solution would be to have the current NM's randomly spawn in one another's locations, so even if you are camping the area you don't know what your guna get, this would at least stop people camping specific NM's and items.