I thought I'd post some stuff about the decisions I made while putting the book together. Somebody might find it useful.
I plumped for the standard black-and-white format. First because it made for a cheaper book, and second because the overall look I was after was your paperback manga tankobon. Blurb's page size here is 5"x8". This is a pretty regular mid-size paperback, maybe a teeny bit narrower than your average UK paperback.
The slide-show version was based on a 4x3 aspect ratio, so some cropping and overlapping was inevitable. I fitted the 18-20 frames for each episode on to 7 pages with a new "title page" for each episode. I made the pages in your everyday presentation software - at 10"x16" to increase my dots per inch in the final book. The text in the speech bubbles was 24pt which reduced down to a good 12pt.
Blurbs price bands are based on blocks of pages, the second band being 40-80 pages. I thought I might as well use my full quota, so I had about 10 pages for a bonus feature. I thought I'd share some of the facts that the Agency knows about some of the main characters.
Also 80 pages is the minimum that would allow printing of the book title on the spine. Well, its not a proper book without that is it? So that decided me.
For the next story, I've done some editing and gone for a more dense frame/page ratio, so that I can buy myself space for another bonus feature. But more of that anon.