Wonderful to hear that you are crafting your Travel Book as a memento of your adventures! We currently don’t have these features, but they are on our ideas list! This does mean that reducing your page count or setting a certain number of photos per page will need to be done manually.
We have some great resources that you can check out on how to do these these:
And don't forget to check out the rest of our HelpCenter articles on how to make the perfect Travel Book!