I seem to have problems at crafting even the simplest ground tiles to have some sort of coherent style.  I really like where the grass is going on the bottom set, but I'm having a hard time making the ground underneath it match. I don't want it to just be a solid ground color under the grass, but I'm not really sure what to do other than rocks.

After working on the tiles in the upper part of the image, I realized that they are pretty damn noisy and therefore ugly, so I went for more of a sloppy/blobby/paintery style with the grass below that.

I don't really know exactly what I'm looking for here, but maybe just a little guidance on how to approach the ground below the grass, or any comments on any of it that might be helpful to me.  I've never ventured that far out of the realm of super lo-fi stuff and I want to make my next project look as good as I can possibly make it! 

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