Oh, I like the working small. You can sell them more easily, and
it is a challenge as well. One thing you can do is block off in a sketchbook various sizes with a ruler. Then do sketches that way too. This is an exercise that really improves design skills etc. It really helped me! It forces you to try risky things, like offsetting the main object or running off the edge in certain places. The FaceBook icon is an example of a small space with an edgy composition. The viewer's eyes and brain tend to fill in things, and learning this trick, will engage the viewer even more! When you do it on paper first, there is less $$ spent on paint etc. Going back a year or two later and revisiting your experiments can be fun too. I think you are well along in your style, etc. So you may be ready for a "new thing"...

I've done small pieces...using pastel pencils. I think they invite the viewer to come closer, and that creates a nice intimacy too!

Small pieces lend themselves to kitchens, bathrooms, and hallways too.