As for the leveling of enemies, I liked the idea NeBy had about some enemies just beginning the game at a higher level than the PC and still levelling with the character. The only thing I would change would be the "stop watch," if you will, for enemy levelling. Having enemies level with you until they hit a certain level sort of sets up a "milestone" leveling system, where the player gains ground over enemies at discrete levels. That is, if you take the guys that begin two levels above you and level with you until level 20, you remain 2 levels below them until you hit level 20, when all of a sudden you begin to gain on them. Instead of having that stop time, have enemies level with you, but at a significantly lower rate. That way, instead of having the milestones, the player continuously gains ground on the opponents, not quickly, but enough to where each level shows a noticeable increase in the player's mastery of skills and prowess in combat. This, coupled with opponents learning new skills as they level, will keep the combat fresh and the player gets rewarded for the hard work they put in to level their character.
Good thinking, kenchi. Yes, that would indeed be an improvement. That way, instead of an artificial rather brusque milestone, the 'milestone' would be spun along the way, and not suddenly gaining fast at level 20, for instance. I know what you mean (stopwatch); I thought it could be smoothed over by maybe making more groups, so it doesn't stand out as much, but your idea is better. Such a system would really work, get rid of all major problems of the current OB's one, and wouldn't be too complex to implement them.
About your 'high level' regions...well, I'm a bit less enthusiastic. It should be done very carefully (if...). Maybe at 'cave' level or smallish region where a certain type of opponent lives, or something. But I don't like the idea of complete area's where, for no apparent reason, ALL critters and beings are suddenly uberpowerful and you can't show your face in half the world. Not much of an open world, then, would it? And it wouldn't make much sense neither.
As for those who want to get rid of levelling altogether, because it's 'natural' to progress and become all-powerful: it may seem like reaching God-mode is fun - and it actually is, for a while - but then it really starts to get annoyingly boring really fast. Besides, it isn't necessarily *that* obvious that the world 'does not revolve around you' in an RPG. It sort of does, actually. Getting rid of the levelling system altogether would make you get 'visibly' stronger, yes, but ofcourse, the annoyance comes forth *because* we know all creatures level in the same amount with you. If implemented differently, as I and some have already suggested, it would get rid of the drawbacks, while leaving it enjoyable for a far longer time. Besides....seen from the perspective of your character; why *should* YOU be the only one that improves himself? Other opponents can improve themselves as well, after all, so why would it be more 'natural' that you're the only one improving? A level system does just that, in a rather feasible way (AI ain't THAT advanced they can really act/improve as (well as) a player, after all). The levelling in OB was done badly, true, but if implemented well, instead of looking at it like the opponents level with you (this is meta-knowledge, after all, it's not from the viewpoint of a (your) character) but rather that they too, are improving. This also makes sense, instead of just claiming the only logical things is that you increase while the rest grows increasingly weaker and weaker.
And also;while I'm all for using logic and a rationale in every game, a game still must be fun, in the first place. I'm all for making things more 'real'; reality is a great good, but only to the point where illogic and contradictions are avoided, NOT to the point we get a second 'real life' kinda environment. I play an RPG not so I can have a repeat of every day life, after all. I want to have fun doing things that I can't do in real life, as long as it remains fun. This means; no stupid silliness, but also no boring reality stuff. That's why I only partially accept the complaint about there being too many forts and caves and robbers near the city. Ok, yes, maybe in OB it was a bit exaggerated, but really, I DO NOT want an actual 'real' representation of our world (not even in a medieval setting). Here, the nearest cave is like 30 km away. I don't want the world of OB (or the next one) to have only a handful of ruins and forts, and a cave or two in a radius of 50 km, nomatter HOW realistically that may be.