i dont know if the map gen already works like this, but maybe there could be shematic presets of proven map patterns which you can modify trough certain variables. Dual Gap Style (sorry), setons style, plateu corners, plateu mids, river, lake whatever. boiled down to its main characteristics which are proven trough 1000s of matches to be a gud map. e.g. its basically canis but looks flat and empty like crater at first. then let map gen do its magic in modifiying it to a new map with the choosen parameters. it would somehow defy the whole point of having a mapgen but in theory the aim would be get new but more predictable outcomes.
ofc the possibility to create maps out of nothing should still be the main feature.