I've not had the time to read all the responses, BUT, ignore the quilt police!
Make the quilt you want from the fabrics you want. I think it is something that grows on you, anyway. If you don't notice the difference, then don't worry about it.
I'm assuming by blend you mean 50/50 poly cotton, right? I have to use this quite a bit because I'm limited to pretty much used clothing and used bedding. I find I do use the 50/50 blend often. It works up just fine. The problem is that it will pill after a lot of abrasion. All cotton won't. Otherwise, with 50/50 I don't notice any difference. Well, once you get used to it, all cotton is nicer, but until you get to that point...
It's sort of like telling a new piano player that their keyboard is junk. It might be, but given time and experience, the keyboard is good enough that the person can learn on and actually probably even make music with. Given enough time, the person may disdain their new keyboard for either a real piano or a Clavinova, etc. But in the meantime, keep using the keyboard...
Don't throw away perfectly good fabric. I use what I have. Only people who have a lot of choice can afford to be so "picky" about their fabric. :)