I looked at Mediterranean using default map Big River.gbm
Everything from the color of the water to the mossy rocks and textures look very nice.
The secondary grass surface texture was used quite a bit by the map designer for Big River.gbm - this looks good when using forest/evergreen tilesets because of the minor color variations between grass and secondary grass surfaces. The deep orange colored secondary grass of Mediterranean does not integrate well with the primary brown/tan grass surface texture - at least on this map. I noticed the same thing on wciows Swamp tileset where his snowflake/fractal secondary grass texture repeat often.
This isn't a problem on maps where secondary grass textures are used infrequently. In fact, there really isn't a problem with the color variations on this tileset or swamp. The problem is, we need more mappers making tileset specific maps which showcase these unique texture features to their full visual advantage.
Nice artwork and colors titi.