Got in some work this morning on the graph styling. Will let you set colors, shapes and borders on nodes, and line width and color of edges. The first editor that I am maybe half done on will be for the overall graph, then a second pass will add to the individual node and edge editors so you can call out an important room in red or with a star shape, or put an arrow on the downhill end of a slide or make water edges blue. Thinking about custom defaults being different for particular types of nodes and edges too, but may not go into that.
Another thing that will be coming pretty soon is to add theme tagging to the hooks and oddities tables so that there can be different lists of set dressing in a castle vs a temple vs a creepy horror setting. You'll only generate a litter of corpses if going totally random or you want stuff like that.
Lastly, I'm thinking to add tweak buttons to the node editing dialog (+Trap), (+Hook) (+Monster) (+Treasure) (+Oddity), so you can just add a roll for one of them, not a total reroll.
Still mulling ideas about other mapping styles, more monster lists to add in - maybe a branch that does EPT lists instead of D&D, maybe swap in lists tailored to particular OSR rules instead of my personal mish mash. One possible map style would be to draw up a set of semi-geomorphs and record for them the points at which room numbers would go, so they could be tiled onto a canvas, room numbers overlaid, and then contents generated to match the room numbering. The result would be a traditional looking map with some flexibility and nicer looking than I could probably procedurally generate from code.