Releases and Versioning
Please consider to add a release cycle to this project with proper release notes and version numbers. I think this makes it more feasible for authors to hand in a final version of the submission with updated source files after the initial submission was reviewed.
Modularity
Please consider to use the aap-template.tex as a base file (or make it at least optional with examples) which includes several fully author-controlled form and content files, such as author-specific packages, commands, content, appendix, acknoledgements. Thus the authors only have to edit included files and can leave the aap-frame pinned by this repository untouched.