I do not express the feelings of the entire staff with my post, so please read them as my own:
We could technically already do this solely with WorldEdit and WorldGuard, by defining a region and applying just one player to it. The issue with that is then the whole purpose of Towny is completely thrown out of the window. Also, when you'd want a friend to build with you, you'd need staff to come add/remove them and that can pull staff away from other players that might need some more dire help. With Towny you have complete control of who can build where, and to what extent. I understand that the price may be high and seem pointless if you're the only person in the town, but I was going to do that originally as well, before joining my current town. I wouldn't worry about your land not being protected either, I had been here since June 21st, and no one had touched my land, we have a very kind player base, as I sure you know. So grief isn't really that big a concern here. Thats just my two cents.