Tony Vargas
Legend
You could leave monster exp values alone and just have /very/ slow leveling at higher levels...The only reason I don't is that I don't want to bring back wealth as XP and 1e style force feeding the party with gold to force leveling, and I'm not sure how I'd well balance XP for challenges when that XP would need to increase exponentially.
...or, you could make quest/story exp awards increasingly significant at higher level.