It's a beauty! Glad you have your answer.

Love the quilt and colors you chose. If you still have more of these fabrics how about a strip of black as its been suggested, then add diamond surrounding in the black made from the colored fabrics so it will look like they're floating then another strip of black to the outside of them. One way to use up the scraps leftover plus this will show the diamonds you have in black come up in the opposite colors.

That's a gorgeous top! Glad you found a solution. Can't wait to see it.

Very pretty!! I do like the idea of doing a staggered pattern with black between - the staggered pattern will not draw your eye away from the body of the quilt but will definitely enhance the lovely stars - possibly simply sections of colored squares or flying geese with black.

If the quilt center is large enough to cover the top of your bed. I would put a black border on and make piano keys long enough for the drop to cover the mattress. You may need a dust ruffle to hide the box springs, if you are going to use it as a bedspread. I would make some sort of pillow covers too.

BTW your top is gorgeous.

Piano keys would be striking!!

I did this with a panel I needed to enlarge. It really turned out nice.

Update: so I never added the border, kind of stopped quilting for maybe a year? Then in the summer of 2019 I pulled it out again to start up again on it...went to Fabricland and they were out of black. So I stopped quilting again...then I just pulled it out last week and added a border! Yay! I didn't have enough black to do another black strip and guess what, Fabricland has no black lol

So now I'm waiting on black and Im debating if I want to pay someone to quilt it, tackle it on my little emerald 118, or wait until Fall when I might upgrade my machine for the first time.

(and I've continued to work on another quilt top, no putting away the machine for another year)

I've attached a picture to show you, if you are interested

Looks great. A black border around the squares should look just fine.