I agree with all of these (a tall order for you!) but the first thing I look at is the completed size of the quilt and the size of the blocks.
Also, if you can include variations for different sizes that would be great. It can be a lot of work to change a twin or crib pattern to a queen or king. It can take me days to chart and calculate if it's a difficult pattern. I've always thought that, if knitting patterns can include directions for various sizes, why can't quilt patterns at least give fabric requirements for other sizes.
Good luck in your venture!