It depends on what type of "touring" you are looking at doing, sag, creditcard, self-supported or somewhere in between? What is your weight, how much gear will you be or can you see carring? Where will you be touring, smooth asphalt roads or dirt roads, around Minneapolis or other places in the world? Also, consider what type of brakes you will be using or the largest tire width you can mount.
All of these questions should be considered before deciding on what type of rims to build. Also don't just think about the next tour but down the road, what can you see yourself doing in a few years.
Journey On
Chris