To make it clear what I believe a region-based leveled list to be, I'd describe it as a system where the items you find are first and foremost determined by the region (or dungeon within a region) that they were found in. For example, you'd have a greater chance of finding, say, Netch Leather armor in the Valus Mountains, and Colovian Fur Helms in the Colovian Highlands region.
I was wondering about whether or not people had ideas about how feasible this would be? Or whether they find the idea attractive?
Looking through OBSE, I find commands like this:
GetCurrentRegions - returns an Array of all the regions in which the player is currently located, if any. In interior cells generally returns 0. Regions in exterior cells can overlap, therefore it's possible for the player to be in several regions simultaneously.
(regions:Array) GetCurrentRegions
But it doesn't deal with interior cells, which is where you're going to find most loot containers.