This is pretty similar to one of my ideas; maybe this could be part of it:
My idea is this: There is an option to enter a map-- It’s just normal Bro-Mon, but with a map as a thing added to it. In the map there are levels. These levels could include Bro-Maxes or regular Bro-Mons that you don’t catch (technically just very weak Bro-Maxes). There are 5 areas: Grassland, Desert, Arctic, Jungle, and Volcano. At the end of every area, there is a very strong Bro-Max. You can choose different paths, and collect items along the way.
Anyways, that’s my idea!