Matthew,
You are correct. Head Tide would be a reasonable stopping place in the distant future. In addition to the manpower and money considerations that have been mentioned, one should also keep in mind the maintenance requirements, especially mowing. While there have been several posts about power mowers, much of our right-of-way contains stumps, rocks, and small gullies, not to mention extremely steep slopes. ROWMOW1 is a good start, but only a start. Another factor to consider is rider patience. While rail fans love long rides, the average family does not. Lenthening the line is what we all want, as it builds vounteer and visitor enthusiasm, but it is a complicated process involving manpower, money, and the factors that I mentioned
-John