I think it would look better with a border in any case, to frame your blocks.
If this is helpful at all, I just put borders on a quilt that had setting triangles all around the edges, with every edge on the bias - ack. I didn't have enough fabric to cut them any other way, so I tried to handle them as gently as possible, even while frogging. They didn't lie completely flat, though. I managed to get the border on by using the walking foot and pins, with the stretchy part on the bottom and the border on top. (I tried the reverse as an experiment and the bias stretched immediately.) So, you might try that if you're going for a border.
Hugs,
Charlotte