String Piecing

Back in March I decided to try some string piecing. Not sure just what got me going, but I was having a good time of it. Over the next few weeks I plugged away, and wound up with 16 blocks. It got put on the back burner for awhile as writing projects intervened, but yesterday I got back at it and did another 8 blocks. (I must have done a few more in there somewhere because I have 43 blocks total.)

While I'm using true scraps—and having so much fun remembering just which projects the strips originally appeared in—I'm trying for a little consistency by including red and/or turquoise and/or black in every block. I'm piecing on newsprint, with a white strip diagonally centered on each square.
I'm using a 9.5 inch square ruler, so my blocks will finish at 9 (it's the biggest one I have) and I'm trying to decide how big to make it. If I make it 7 blocks both ways, I'll wind up with a 63" square, but I might go with 8 blocks one way to make it long enough for a tall guy (like the one I'm married to) to cover up comfortably. I'm not even sure I'll be keeping it though. 
Do you have a favorite/most useful size that you tend to make?