The first thing that comes to mind is the coloring of your quilt. I would not use darks, keep your colors to light to medium color range. I personally use a washable marker by Dritz. It does show up nicely on light to medium colors. If you don't necessarily need to do a pieced block, then there are many quilting stencils/patterns out there that are beautiful just done on a piece of material where you don't have seams to deal with. You could even do a whole cloth quilt and just use whatever designs you choose to.
I have a friend that has limited eye sight and she finds hand quilting and needle turn applique is easier for her to do then machine piecing. If you're interested in applique, PM me and I'll send you some sites that I frequent.
She's using a size 10 between, which is a good size for someone starting out with hand quilting.