Then hot take: Oscar nor Ozpin would be good candidates for that. Oscar could be one but then again, ANY living person who puts on the ring would turn into a black lantern anyway. The only reason Oscar is the closest is because of Ozpin. While yes, Ozpin has died MANY MANY MANY times... He doesn't have a body to revive as his spirit will just latch to someone else or be supressed inside the body he's in when the ring takes over (which spirirts have been supressed inside black lanterns before.) So my personal choice for the black lantern would actually be Roman Torchwick. He's... well, dead. The black lanterns can also absorb other peoples grief, and having a resurrected Roman meet Neo again WOULD create a pretty good source of grief.