Advice on how to finish quilting

I’m struggling to decide how to finish quilting this quilt. So far, I’ve used grey thread to follow the grey background fabric, but I’m not sure what to do with the other parts.

I’m a little disappointed with some of my color choices, as the lighter green doesn’t stand out as much from the background as I thought it might.

Any ideas about quilting and thread color will be appreciated! Thank you!