This is awesome. I'm using it to make DM and player's versions (less info but more stylish). Small sugestion, add an option to make the grid number more readable over objects.
There are some curuious perks. "Hexes orientation" changes object creation/distribution on the map (feature?). "Rugged" has the same effect, but only on "Pointy topped" hexes, not on flat or tilted.
EDIT: Playing with the url to retouch it without generating a completely new terrain. Is there an UX way to do refresh parameters without changing the seed?