My personal thought is changing code to adjust the exp reward for random maps is certainly the wrong approach. Updating the style maps would be the right thing (don't do something in the code if it can be done in the data files). If new styles are added but the exp isn't set right, that really isn't any different than someone putting in a map that gives too much treasure or too much exp. You don't go and change the code to try and fix such maps, you fix the maps. Same would hold true with style maps. That said, if this really is considered a problem, another approach would be to change the random map code to reduce the monster density. The problem isn't that the individual monsters are worth too much, the problem is that the random maps tend to have a very high monster density. And arguably, at some point, higher density doesn't make it any tougher.