120-125 does indeed take a while, would be nice if there were a few more 120 zones.
140-150 is fine though imo. Slower level progression at the end is necessary for the game's longevity. Ever played original D2? 97-99 took at least as long as 140-150 if not longer because Baal was the only place to gain XP. At least there's a few options in Median.