It's still slow going but I took another step towards completing the angel quilt. After some pondering, I decided I really did want to run some piping along the frame, and that the yellow-green batik would do the trick. Of course, I'd never know for sure if I didn't just do it. It'd have to be on the bias to make its way smoothly around that curve at the top, and with only a 9 " width of fabric to work with, that was going to be a lot of piecing of short strips. Unless...
...Somewhere I'd read that if the curve is gentle, the strip does not have to be cut on the true bias. Slightly off grain should provide enough stretch. I placed my ruler to cut a cut the length of the curved part only and found that the angle was less than 30 degrees but the fabric still had ample give. I cut a 3/4" strip, then cut two 3/4" strips on the straight of grain long enough for the straight side portions. Yes, I was insufferably pleased with myself for coming up with that fabric stretching solution.
Inserting the piping (folded in half and leaving just 1/8" exposed) probably would have been easier to do had I done it before my careful pinning in place of the frame. On the other hand, it wasn't that big of a deal to move the pins out far enough to accommodate the piping's seam allowance, then re-pin through all layers close to the frame's edge. I top-stitched with invisible thread the same way I secured each layer of the background (see this post), so there is consistency in method, if nothing else.
When I stepped back to view the results, I was pleased at how the bright piping helped draw the eye inward to the angel, exactly what I felt the piece needed. Of course, I soon started second guessing as to whether the piping was too bright, but I still plan to do some lightening up around the angel itself which should help produce a more cohesive glowing effect. Well, at least that's the plan. Much further to go on figuring out the additional details in this design.
Now it is back up on the design wall with pieces of potential side border fabric hanging on either side, waiting for me to make up my mind if either will work and what else I'll do to pull this design together.