TL;DR Add the ability for maps to have different multipliers of DP and XP if your using a certain ability.
If a map has an op ability that can be used to cheese the game, the multiplier should be changed to support the fact that players are literally putting no effort and getting DP. This allows the easily sentry exploitative map, Beach House (once it gets a multiplier), to have a higher multiplier when nobody is using sentry and thus reward the players for how well they are trying.