The problem with asking for opinions here is that you get as many different opinions as you get posts!
I like no sashing on this one. It's done with black and brights-which lends itself to the modern quilt family. I'd add another row of blocks to make the size you want and quilt and bind with no sashing or border!
Second thought-How fun to have a live in sewing buddy!
Third thought=Where's the mess??? I don't see any mess? Wanna see mess? Come to my place!