These are all really cool, Jed. Love the sense of mass and weight with limited lines. But, then I often 'go for' that.:)
That's always been my thing too, but lately I've been going for a little more modeling and hatching as well. These though, I like to keep simple. This one might be one of my favorites. having a great time with these. After the first 20 or so I had to really stretch myself to come up with new and interesting monsters, and the more recent ones are the best, and comprise most of the ones I'm sharing on my blog.
I get that feeling occasionally, too, that I may just be copying myself, and 'is there anything I can do differently to avoid it?'.Sometimes I just slump at the wheel, and say, 'well, whatever, I still like this shape or expression', etc.Some things may remain perennials for us. Do enjoy the unique twists, tho. In your pics, too. These are all begging for some story/book exposure.