When I tried to make the edge tiles with the pattern below, they looked funny, so I reverted back to my original pattern and added some brighter highlights to give it more depth.  I also rounded out the corners and tweaked the shadows along the bottom of the grass:



Or with more contrast:

This is awesome.

Shading feels pretty accurate to me, although I think the reference photo has more contrast.  Here's a couple things you might try:

* Use a much lighter, less saturated background color, or
* Darken your shading colors a bit, or
* All of the above

I upped the contrast a bit and changed the color of the random plant.  I think it stands out a little more now.

I'd rather she not appear overly muscular.  I've toned down some of the highlights and shadows here, but I've also shaped them a bit to give her what I think is a bit more volume.  How's this look:

Okay, I'm kind of stumped on this.  As for "more detailing", notice how some of the right walk frames look rough.  I just want to make sure the walk animation looks decent before I clean it up.  I'll try widening her shoulders a bit on the front frame and re-shaping her torso, and see how it comes out.