The rolling countryside where you live would be ideal for a SS or even a fixed gear, Bill.

You don't have to be really fit for a fixed gear. It comes down to choosing the right gearing, and going from there. It's best to choose a lower gear initially, and change as you get more and more comfortable.

I started with a 39-18 set-up, quickly decided that I wasn't that comfortable with it for the terrain I was riding, and went to a 39-17 that I stuck with for some years. It's only comparatively recently I went to 39-16, and I am still not entirely comfortable with it when climbing, although downhills are easier (we have some decent climbs around here).

One of the beauties of fixed that can be quite difficult to relate, is the "perpetual motion" on the pedals that comes from just riding. There really isn't a dead spot on the pedal stroke, because the bike won't allow you to have one as you would on a SS or geared bike. At least, that is what I feel (others may disagree).