Travel appliqué put together--and borders?

I decided to do the "on point" diagonal setting for these blocks, but to take a row off at the bottom so that I didn't have to make more blocks.  The top as is comes to 64" square; I'll add a couple of borders, which will make it a good size for a throw on our couch.  The gray used for the setting triangles and corners is a little lighter than that used for the squares--an accident of different dye lots for this Kona cotton, but I actually like the slight contrast.  This arrangement leaves me with a couple of "orphan blocks," but I have good uses for them.  One of them was not a favorite; I can use it to do some trial quilting.  The other was a much more intricate design than the rest, and in a different style.  I think I'll put some borders on it (below) and make it into a wall hanging; the single block is 15" square:

Then I auditioned a couple of different border possibilities:  a sawtooth border and a plain strip (one above the other in photo on left below).   Better to combine them--first a plain strip and then sawtooth outside that one (center).  I also tried out a dogtooth design (the "mountains" on right), but like the sawtooth better. 

Next is one of my least favorite parts of quilting--doing the math in order to figure out how to get the sawtooth triangles to fit neatly around.  This is what usually keeps me from doing anything except the simplest borders!  But since I'll be inserting a plain border before the sawtooth one, I should be able to size that border in such a way that the math for the sawtooth pieces comes out.  This is a task that must wait until I'm feeling sharp.  Now, if my mother (former math teacher) were alive, I could give her the measurements and she would enjoy working it out!