Some kind of waterborn adventure is a good alternative to hiking, because you can find all kinds of bush areas to get into really private settings. It is amazing the little streams that are everywhere, and meander through private property in complete seclusion for miles. Using these depends on your local property rules. Problem with a lot of cycling is that you cover a lot of road, and most of it is pretty built up.

When you say 22 tooth, I think you mean 22 inch, and your 21 speed probably already has a gear in that range, considering your cranks, and wheel size.

I prefer racks to trailers. And most people do. If you know about AT backpacking, you know you can get by with a pack of gear that weighs as much as a lot of empty trailers.

You can get a pretty good real frame for touring from Nashbar for about 100. So whichever of these two frames is the least worst, rather than trying to build one out, get a Nashbar frame. I build my own frames but for the kids etc... I can't afford to pass on a Nashbar frames when the specs work out and they have a sale.