Note on the part ² content, a better method than splitting it is to archive the old content into an rpa file that has to be downloaded separately and added to the game folder. This keeps the game to a single program, no real divergence on your end between the versions, and the apk system can remain the method of updating for users.
not really, the only catch on my end has been getting access to the folder sometimes, but most of the droid versions have a secondary folder to get around the permission problem.
With that admitted, doing it that way would require the user to put another archive in every blue moon and thats about it. Well that and the initial install. The rest of the time it would just be apks as normal