I think there should be more stock command pods, Like a high capacity 7 Kerbal one, and a 2 Kerbal one you get after the mark 1, but before the mark 1-2. As well as a command pod built specifically for rovers.
I watched at one of the causeways. I got lots of pics. And one of the explosion. Will post when I get them on my computer. - - - Updated - - - I thought that it occurred at max q. I think it was a pressure issue, a problem with the second stage engine fairings being under too much pressure.