My feelings on this is that you will never be able to sell a quilt and get what it is really worth. Right now with the economy the way it is it is hard to make money on any craft projects whether it be quilts or more simple projects.
I think your prices you list here seem pretty reasonable. You can always come down if you really want to sell them and they are not selling at this price. I guess too, it depends on the quilt. How hard is the pattern and what quality of fabric did you use? Lots to consider when you are trying to sell them.