Another option is to limit the number of heroes – for example, a maximum of 4 heroes can be on the map. I've already suggested making this a setting in the map and template options – specifying the maximum number of heroes allowed on the map. Interesting game modes could include a maximum of 4 heroes or a maximum of 12 heroes. After all, the number 8, which is currently the default, doesn't seem to be justified. I don't even know what NWC based this default number on when they introduced it.
More precisely, it should be 5 heroes.
Because more than 5 heroes don't fit on my screen.
And I don't want to change the resolution from 960x600 to something else, because 960x600 is the original game's native resolution.