The way stones and dirt are done by Tony Redmire in these two pieces really grab my attention:

http://68.media.tumblr.com/a72a9f367363d83ca70227d13f18c174/tumblr_n2suqhtYYT1tvdasoo3_1280.png

http://68.media.tumblr.com/8ab54180ed53c2c14900a837a1f30999/tumblr_n2suqhtYYT1tvdasoo6_1280.png

Here is a side by side of what I'm talking about.

http://i.imgur.com/n2J6WNx.png

There is a clear repeating simple geometry which makes up the texture, and very very few pixel lines are ever anything but 45 degrees. I've tried for several hours to replicate the effect but to no avail. It's outside my typical style which is part of why I really want to learn it. Does anyone have any suggestions for an order or a general method I might try to get the effect. Really tips in general for drawing with simple low pixel geometries like this without it looking repetitive and without compromising the complexity of the actual piece would be great. I'm okay with spending a lot of time on it of course but anything which might get me on the right track would be great.