I "liked" the french version as well to get it going and replied to it as well since I speak french. Just made some specifications to reflect what has been said here to say that it's not that we can go from 1 to 50 in the same region (Black Shroud, Thanalan, La Noscea) that is the big issue but that the feel of progression is non existant.

That this could be solved by making each sub-zones of the big regions different but still using the same eco-system theme like the drawing of the OP express http://seahorror.com/thoughts.jpg. So that each sub-zone would have it's own flavor and monster types and you would feel a progression by advancing to the next sub-zone.

Would be like combining Saruta, Taronhgi, Giddeus, Buburimu and the dungeons like the maze of shakrami and the towers un Saruta to be under a "seemless" region formed by all these different sub-zones with their own flavor but all with the same type of eco-system in the background.

No matter that all 3 starting area offer the same progressions and that we can go from 1-50 in either of these regions, it wouldn't feel boring if it was like that with different sub-zones. They could still reduce the starting regions to be from 1-35 and then Coertas and Mor Dhana to be 30-50.

[TL;DR] Anyways that's my input on it, I know it has been mentioned by others and I said pretty much the same thing in a earlier reply but I just want to stress the fact that it's not the fact that it's 1-50 in the same region (zone) but the fact that it's the same exact copy-pasted environment everywhere you go in the region. Making each sub-zone different but still under the same theme and distributing monsters accordingly would be the way to go.