Share to PDF defaults appropriate for people outside of USA

I'd like to change the defaults when sharing to a PDF to not be Printing or US Letter size. I would like to have Viewing as the default optimized for, and then when Printing have it default to A4 rather than US-Letter size.

Some reports take quite a while to render, and being outside of the USA I never want the default PDF that Aha has spent time producing. Slowing down my usage, and I guess putting extra unnecessary load on the Aha servers.