If you use boards to make up the base of the bed, where would you put the table at night?? As you know, there is not a whole lot of extra room in an X-139. If you come up with a solution, let me know -- there are times when I wish we could make the table disappear temporarily, such as when we want to sit side by side on the dinette seats. (This would be handy, for example, when we are looking at topo maps together, to plan the next day's hiking route.)
West LA is slightly better than Orange County when you are heading up to the Sierras -- instead of slogging through Long Beach and the South Bay for an hour, you can hop on the 405 north of the airport and you are on your way. You could probably get to the Sequoias in five hours or so.
On the other hand, when heading out to the desert (including Utah), West LA is at a slight disadvantage, since you have to cross through the heart of LA to get to the 15 North. Folks from other parts of the country should feel lucky that they don't have to plan their lives (and departure times) to avoid sitting in several needless hours of "rush hour" traffic.