I'd go with a bright - a favorite color of whoever it will be for? Your blocks look great!

I almost think a purple would be pretty! It really just depends on who it is for, black and white will match pretty much anything!

Greeeeeen. I love green. :] I want to one day make a black and white and green quilt.

I would audition all kinds of colors and periodically pull the color away, look at what I had, and start over again eliminating some and reauditioning others. Constantly looking at a "no sash" possibility. Have fun. Please show pictures of your road to completion.

I'm all about the red. Black and white with red is classic. Beautiful quilt top!

Sashing is very forgiving if your lines aren't perfect. I would choose a grey sashing and then add a bright colour as posts.

What do quilters do? We lay different colors down till something goes, oh yeah, perfect. Now and then it ends up, oh well, this will do. Have fun, this keeps me out of trouble with the neighborhood.

I agree. I would skip sashing too.

I think dark red would be a great choice. I really love your pattern.

If she skipped the sashing, that would mean more blocks were needed. Color is such a personal choice. I would love turquoise or red. But most importantly, what would your recipient like? How wonderful that they would have the opportunity to participate in the creating of their quilt. What colors are in their bedroom? Luckily black and white can pretty much go with anything. The color(s) you choose though will have a dramatic impact on the final look and mood of the quilt so do as others have suggested and try several layouts of blocks on different fabrics, even once you have decided color! If you have a design board that would help tremendously.