I worked up a few ideas in EQ7. I happen to be working on a variation of Omigosh myself (replacing the Shoo Fly block - so the version below looks slightly different). My EQ7 versions don't have as wide a variety of color as your quilt or mine, but it gives us a general idea.

1st pic is with a piano key border ... I think it's very distracting (oops .. I forgot to add a white inner border, but I don't think it will help much <g>).

2nd pic is with a diamond border ... slightly less distracting

3rd pic is with QuiltE's suggestion of using the double 9 patch in every other block around the border to extend the chain. Of the three ... I like this idea the best!!

One more ... I kinda like this too. I put a 4" white border then a series of 1" different colored stripped borders followed by a 4" white border. I like the frame. While I like the look ... the thought of 80" long 1" strips frightens me!!!

or look at fabric with graduated color going across it in the shades you used in your quilt. it's lovely by the way!!
sort of like this border fabric I used on one-

What about a wider white border and then scallop the edge? You could then bind it in your favorite color from the quilt.

I love, love, love the quilt!!!!! You have been a busy quilter. :)

I thought about this one a while. Here's what I'd do, I'd put on a narrow border of white. Then I'd add mini 9 patches but make them match the colors of the blocks as you go around the quilt and then another narrow border of white and white binding.

Love the quilt as is. I would skip the border altogether!

I like DogHouseMom's third example the best. It keeps the delicate-ness of the center, but is much more interesting than a solid white border. I feel it "completes" the quilt beautifully.

Your quilt is awesome. I would go with a simple border and let your beautiful quilt shine

That is just BEATIFUL and AWESOME and INSPIRING!!!!

I like QuiltEs idea also, I think the piano key would fight with your beautiful, beautiful design.