One thing you can do is try to render things separately so in Photoshop you can run different filters and use different settings on each element. You can also try running the same filter with different settings on two copies of the same layer and erase some parts of the top layer to get a more natural and varied look to the image. Start with two elements from those images you showed us and try to replicate them. Maybe the background and one foreground object.

 

LukeA

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