That clears things up a lot, and I changed my downvote to an upvote. EDIT: To be clear, I disagree with you.

My thoughts on your disadvantages list:

• Flush toilets do create additional dependency on water, however if one already has running water and depends on it for drinking and washing, how significant is the additional water dependency for flush toilets?
• The reason flush toilets use potable water is an economic one. It is simply cheaper to use one unified water system instead of two, when someplace already has running water. The cost of the wasted drinking water is negligible compared to the cost of building a second plumbing system.
• This point is the most interesting to me. I have no information on the usefulness of human manure, and would be interested to know if human manure would have a comparable market value to cattle manure or synthetic fertilizer. I am skeptical because of the tendency for human waste to carry human diseases.
• I have no disagreements with this disadvantage, but simply feel that the vast, vast majority of people would be willing to pay for the extra cost in housing if they already had indoor plumbing.