I love your quilt! And the fact that you did it on a treadle is so cool.
I have two treadles. One is a Singer 127 from 1906 and the other a New Home from 1912. I have meched both of them. (I am a certified sewing machine mechanic, but it is not hard to do.) The Singer had not worked for at least four decades when I got it and the decals were worn, although the cabinet was great. In two evenings, I got that baby purring. The New Home, on which both decals and cabinet is in great shape, is running great after maybe 6 hours of work.
I have the Singer 127 in the living room, in front of the window. You have inspired me to make my next quilt on it. I believe I could put a walking foot on it and quilt it as well. I haven't tried free-motion quilting on it yet.
Which brings me to a tip for you: You can free-motion quilt on ANY machine with a Stoppax attachment. This was made in Denmark 50+ years ago and is a heavy gauge wire which you attach to your machine. The only source I have for these is e-bay, usually under darning attachments. Thy usually go for $40-$60 each.
Now for the person that has a Singer 27, a Singer 66, and a Singer 15 and was wondering which to fix first? The 27 is a good straight-stitch machine on which you can zig zag and do other things with the right attachments. The 15 is excellent for piecing and quilting and is a wonderful, adaptable machine. You can use attachments there, also. It is an excellent quilting machine and can be used on a frame, such as John Flynn's frame. It sews nicely. The 66's value lies in the fact that it has more power than the other two and can generally sew through thicker things. Again, you can use attachments, but if it is a 66-1 model, they will be hard to find as they attach in the back and are specific to the model. My vote is, fix the Singer 15 first.
Cricket