The New Rural Road...
Unlike the other films we've watched, Straight Story follows Alvin Straight on his journey not away from the rural Midwest, but rather through it. The rural road works kind of in an opposite way for Alvin, unlike how we've seen it work in other films. Rather than cause him unbearable grief, it gives him the opportunity to fully go over his life, and in turn, find himself.
Alvin decides the take his journey from Iowa to Wisconson in a very untraditional way: on a lawn mower. The riding lawn mower in itself can be associated with the rural country. I think here we get the sense that Alvin represents everything rural. Yet unlike the other movies we've seen, he is not a horrible, racist, rural person. He is actually quite nice, and pleasant to be around.
Perhaps the reason he is able to actually find himself while on this rural road is because there is really no chaos for him while on the road. The urban road in other movies we've seen have always been at times a bit hectic and busy. Here, Alvin is able to very slowly make (over a month) progress to his destination with limited distractions, thus allowing him ample time to think about his life, his mistakes, and his regrets. It is possible that if he were on a city road, in a traditional road vehicle, he would have had more distractions to keep him from thinking, and less time to do the thinking, and could have possibly missed his road of becoming.