As a former real estate broker, I can tell you that building can be a very stressful situation. However, buying and remodeling isn't much better. I would give your current market a look, online or however, and then decide....timing is everything. Also, if you think you will be there a long time, think about doing some stuff for yourself, like putting the laundry on the same floor as the bedrooms, definitely a basement if you are going to have kids, etc. You may also want to look in to whether or not any area has the kind of lot you are looking for right now.
You know, it's all personal taste and needs, I have a 3100 sq ft without a single step in it, except two on the deck leading to the pool-all one story stretched out. It has a formal dining room that we turned into an office and 4 bedrooms, one of which is a craft room/office for my room mate. I like the plans you showed becuase the room sizes are nice...that is really important, to not chop up the space into small pieces, because you will feel cramped regardless of how big it is. My bedroom is as big as many living rooms 22x22, and the living room and family room are huge...but you can about anything with them!
Good luck with your search, if I can help, just PM!!!!