I decided to try the zig-zag pattern with solids; another baby quilt, 36x39. I have a large stash of solids and I thought I'd be able to pretty randomly pick 12 colors, but it wasn't so easy. I'm happy with the mix I chose. Amy Walsh has a great pattern with all solids ("Color Cues") in the April 2010 issue of American Patchwork & Quilting, and she comments in the article that "there's no substitute" for working with solids "when it comes to practicing your color expertise.
Then I decided to play with the scraps that I got when trimming the edges of the quilt. I had to make up a couple of blocks new to go into the piece, and I would have had to make a few more to get enough choice to be 100% satisfied. But I decided that 85% satisfied was good enough for this one below, which is 12x12. (The chalk marks are left over from marking the quilt--they'll come out easily.)
Since I started dyeing my own fabric, I've been less drawn to commercial solids. The colors seem somewhat harsh to me (because of the total uniformity of color), and the most readily available solids for the retail buyer are Kona cotton, which is heavier than I like to use. But it was good to come back to them for these projects. For brights and contrast, they're a great choice.
Another option for solids is shot cotton, which is a much thinner fabric (works even for applique), and which has a softer, more complex look than the solid Kona cottons because most pieces have a different color for the vertical and horizontal threads. This is the fabric I used in the "Spectrum" quilt. My sister was interested in a wall-hanging similar to this quilt, so she bought me a great collection of 60 different Kaffe Fassett shot cottons, 1/4 yd each, and I get to make quilts! Thanks, Cookie.
You can see the shot cottons, along with other beautiful fabric at the "Glorious Color" website.
And then there's the option of using fabric I dye myself, but I've got to do a lot more dyeing before that happens. . .