There's been something that's been bothering me about the terrain - the rivers are always very wide, and there are lots of lakes and ponds with no outlets and inlets. Ponds and lakes without inlets are relatively easy handwave away - they are fed by underwater springs - but lakes and ponds without outlets are less so (in Finland, the geology is not conductive to underground rivers, being mostly hard granite instead of limestone or other porous rock). I don't know how complex the terrain generation system is, but if it were possible to make it produce natural-like waterways - lakes almost always having outlets that flow into another lake or streams that join another stream to form larger rivers - it would make the world more life-like. But then again, the waterways do not have any defined flow direction either, do they? Maybe it would be just too much and would require overhauling the entire generation system....