Adding new biomes isn't something I've ruled out but my immediate plans are to add some options for modern buildings.
Out of interest how useful would a hex based version be for tabletop RPG maps?
for hex based assets we all use http://dgbaumgart.com/works/painterly-game-tiles-hexes/ stuff because it has an high variation and he is working on new stuff right now.
If you make more biomes (which I would also like) then publish them as a separate pack, assuming the price is similar I'd be happy to pay for more of them! :)
frankly I don't even use hexes for regional maps in TTRPGs, I prefer square tile grids for both battlemaps and overworld maps.