Maybe a baptist fan, something traditional, if you want to challenge yourself further, and dependng how your borders finish, maybe some feathers. You could also quilt each block individually.
Also, stitch in the ditch (SID) or a grid would be nice also, if that's what you're comfortable doing.
Quilting is supposed to be fun....and a little challenging IMHO. So do what is comfy for you.
It's a beautiful quilt. You've done a wonderful job.