If I'm regularly creating designs for which I'll need a variety of page layouts — say for example, a Facebook image, an Instagram image, a YouTube thumbnail, and a print flyer — I'd like to create a document preset that includes all of these.

Currently, you can only have one page size in a document preset, but I'd like to be able to designate something like "page 1 is letter size, page 2 is 1920x1080," etc.