Sweetie, your bag is awesome!! As far as underwear is concerned, I think it is grossly over rated. During the summer (which is woefully short here in the Great White North--well, Ontario) I love to wear as little as possible, because come the BIG FREEZE (let's say November to April or so) I have to contend with waaaay to many layers just to comfortable.
Did you actually design this bag?? I think it is amazing and maybe you should contact a couple of magazines about your pattern.