Design dilemma

I fell in love with this design from Kim Brackett's "Scrap Basket Sensations":

 and remembered that I had yardage of a brown monoprint and scraps from the "Buttercup" and "Fresh Cottons" collections from previous projects.  During the first week of the Orca Bay mystery, I made 16 blocks for the center of the quilt and through the weeks added 20 more for a 6 x 6 layout.  Then I ran out of fabric.  I wanted it larger so I bought a jelly roll of "Buttercup" on sale online and made 28 more blocks to finish the designed size:

Here it is with the blocks laid out in order.  Before I start joining the rows I wanted to decide if there was something else I could do to make the quilt larger.  I have more 2 1/2" x 4 1/2" scraps of the colors and plenty of the brown, so I'm thinking about adding a 2" brown border and then a 4" picket-style multicolor border with the brown triangles added to the outer tips to make the pickets.  Perhaps then finish it up with another 2" brown border.  What do you think?

I also thought about a 2" border between the outer and second concentric rows, and made up the difference in the length by adding two 2" brown strips between the 2nd/3rd and 6th/7th blocks, which looked good on paper but not in person.  I scratched that idea.

Or should I let well enough alone?  I would like the quilt to be a little bigger.  My picket border would size it up from 64" square to 80" square.  It would also be a lot of work, making those 128 pickets plus the corner blocks.  I'll have to look at my scraps again and see if I have enough before thinking further