Hey there. I like islands, archipelagos, river-created canyons and so on. But, even with good maps, tool-genned maps with higher water levels, you may not see all the features you'd like... So, I'd like to see a plugin that lets you pick multiple points on a map, assign each point a depth, and choose if it's a river, a lake or an ocean. Rivers have steeper edges, lakes have smoothing and some sand, oceans have sandy borders, lots of smoothing/erosion and will naturally go all the way down to water level. Additionally, choosing 'River' results in a spline calculation between points as though a straight line, whereas lake and ocean treat the selected points as a polygon for the purposes of creating the body of water. Having rivers across multiple y-levels seems difficult (perhaps not, if you're good at 3D splines), but taking a mountain range, say, and putting a river point on each side would create a canyon. Perhaps an underground river command would be a good idea, too. The other thing that this plugin should do is find out if the creation of the body of water will open up any caves, and then fill the empty space with water sources to create a more interesting underwater terrain.
