Look over there

Incidentally, lv 80 doesn't take that long to get to if you opt to exploit a bug (that may or may not be fixed in the 1.2 update :/ ) As of version 1.1, if you do a story mode stage on Lunatic, then exit out back to the title screen to set your save file to Lunatic, then you can do history mode stages with a hidden modifier to experience/gold/weapon drops without enemy stats changing at all (thus we're 100% sure this is not intended behavior). How much of an experience increase is it? Not sure exactly, but my personal guess is that Lunatic's +20 level modifier is being applied. It's definitely noticable though. How much of a gold increase is it? The game will say you got X amount of gold, but if you pay attention to your gold total, you will notice that it increased by 2X (as if Lunatic's 2x multiplier was applied). The weapon drop change I'm just mentioning for information's sake, since it's probably not that relevant. The example I've tested to observe this was a lv 10 map in history that dropped Bronze/Iron on Normal, but dropped Steel/Silver on Lunatic. Then I tested a lv 20 map which went from Iron/Steel on Normal to Steel/Silver/Brave on Lunatic. It stops being relevant when you're grinding for higher levels, as you're probably doing lv 50+ maps then. Those maps still drop Steel/Silver/Brave anyway.