I personally play on the OC with a couple of other people in one small spot, but most of OC seems to be a ghost town, how hard would it be to do something like:
>OC is getting reset in like 2 months
>flag off parts that you don't want reset
>anyone who logs in on the two months gets notified about the reset and is given a message on how to flag off your awesome house
>when the reset happens all the un-flag'd biomes get removed and there is a chance a whole new biome will be in that spot
>your inventory and enderchest do not get reset even if you are in a un-flagged part
>new people are still sent to the NC untill people feel the NC is crowded.
Dunno, anyway those are my thoughts. The couple of hours I have racked up have been 99% on the OC, and if it was fully reset I don't think I would enjoy starting over.