I agree. It saddens me that in order to take advantage of OOO's place-centric levelling, I also need to accept all of the other things about OOO which I don't necessarily care for. Heck I don't even know half the things OOO does.
Even TIE which is lean, still changes things that I would prefer to leave as-is.
I actually had a (rough) idea recently that is probably doable with OBSE.
A scripted level scaling overhaul, based on radial distance from marked locations. IE each city (possibly dungeons and/or dungeon levels as well) are marked with various seed levels. The further you go from any seed, the more difficult the mobs will be. The IC would be seeded as level 0 or 1 of course. Other cities could be seeded for higher levels. Dungeons and dungeon levels could be seeded to override the more general level calculation for more specific control of the npc levels.
It would be entirely modular. Any plugin could add new spawns or new npc/creatures and they will all be handled universally.
It could potentially offer the user the choice between (or a combination of) place-centric, player-centric and other metrics not really possible with a static plugin, such as; time, game progress (not level, some measure of total quests completed or such), entirely random, etc..