Using your numbers, I ran the numbers earlier for my own entertainment, but I guess I will share. You should gain 7.7 inches with a height of 39 inches. I assumed that you measured center to ground. If you measured by pole length, ignore me. It seems like you should get more than what I calculated, maybe I am wrong, thought I would share anyway. First Post, two year member, please be gentle!
edit: I was running numbers because I really like the work you do. I was trying to figure out how the design could be made asymmetrical, as somebody else mentioned. The sewing complexity of doing so seems daunting to me.