What about a straight stipple instead of the traditional curvy stipple? The short length of each line makes it easy to do with a darning foot & I always hear people say that the straight stipples look "more masculine".

An all over quilt lines.

Just use some painters tape to guide you, that way you don't even have to mark the quilt. Or if you have a walking foot it likely has some guide bars that came with it, which is even easier to use. I've attached a photo of my walking foot with the guide bar attached so you can see what I mean. You just line up the guide bar to an existing seam or painters tape. A serpentine stitch would be nice as well (a wavy line) - the the photo you can see this stitch in the narrow gold border.

An an all over meander would look nice too, but it would probably take longer to do.

Thank you everyone. I went with a meander however if I'd thought it through a bit more I think I may well have used my walking foot and guide bar and tape as an extra precaution. I've almost completed the piano key border but may change tack if there's a place at which it will look fine from both sides.

Both sides are very pretty. As for the quilting I would do an overall meandering. Can't wait to see what you decide.

Very pretty quilt. I was going to suggest meandering but I see you already decided. Could you post a pic when you are done with it please? I would love to see it

I'd do a meander or a cross hatch. Honestly I think a meander would enhance both sides very nicely.

Both sides of the quilt are wonderful and an all over meander would probably be best, and suitable for both sides.

Really nice quilt, and however you quilt it will make some lucky person happy.

I have nothing as far as suggestions since you have received so many. I am just so anxious to see the finished. Love the fabric.