fasting2goal,
One extended fast should be sufficient for resolving detox and other health problems, but it is recommended by many fasting authorities to fast for 7 to 10 days two to three times annually thereafter to maintain health and an internally clean body.
Your plan of re-feeding sounds fine and where the body will grow into ever-improving health with the adoption of a Natural Hygienic lifestyle, and therefore avoid the need to undergo any extended fasts in the future.
The body is continually striving towards health, and as long as we give it the right bodily environment to achieve this, then good health will always be maintained.