I just got a post from Woodall's blog which had an article by Dana T. They apparently travel in a toyhauler RV with 10 kids (cannot even imagine it) but she had a lot of great ideas for organizing things or better utilizing space in their RV. I will list a couple of them below but down at the bottom of each article you will find links to other articles she has written. There are a lot of neat ideas that are not terribly difficult or expensive and don't add a lot of weight.
http://blog.woodalls.com/2010/09/kitchen-organization-in-your-rv/
http://blog.woodalls.com/2010/03/mods-that-help-utilize-your-kitchen-space/
http://blog.woodalls.com/2010/05/kitchen-mods-make-my-life-easier/
http://blog.woodalls.com/2010/07/creating-useable-space-in-the-bathroom/
http://blog.woodalls.com/2010/07/creating-useable-bathroom-space-part-2/
http://blog.woodalls.com/2010/04/easy-modifications-for-your-camper/
Not all of us are as talented a carpenter as colliemom but a lot of these ideas could easily be done by some of our womenrv members and they aren't necessarily geared toward a large family but rather towards making the best use of your space.