You could definitely do more than one book. For our last trip to WDW DH took 1200 pictures in 5 days. One of my albums that I'm currently working on a Disney ABC album. Stuff that doesn't really have a theme or that doesn't have a spot will go in this album. Also pictures that are basically the same shot. I also have an animal book, we love to take pictures of wildlife. The animal and ABC albums are the only ones I'm doing with culmination of pictures from throughout the years but they still stick to a basic theme.
I also don't have a lot of time. You are definitely on the path to success with the sorting. If I have a few spare minutes I put kits together, Creative Memories calls them power layouts. Basically you put your paper, photos, and embellishments together in a kit and when you can, go back to them and put them together.
I took a peek at my Disney album and a lot of my pages have 2- 6 pictures per page. It really depends on how much you can crop away from the edges. Just don't feel the need to complete an album immediately. It can get overwhelming, trust me. You do what you can, when you can. It will all come together eventually.
My DH put it best. He said I never want to hear the words finished and scrapbook in the same sentence, because it will never happen.