So, I’m aware of Syncthing for much of the media, which may help after getting things migrated, but I’m wondering if there may be something more like Clonezilla (or the like) for smartphones to more easily copy over apps & media in bulk.
I also know that the Play Store keeps track of installed apps and I can go through it to individually reinstall each one, but I imagine there must be a much better way.
I personally prefer to go through methodically: moving each thing, copying over the settings if needed, and then deleting it off the old one.
It gives me a chance to clean up and delete things so they die with the old device. I can also have a nicer folder structure afterwards and get through a lot of maintenance in one go.
But this isn’t always convenient. You can also do this partially, by using a transfer tool then setting up each thing again as needed.
Whatever method you pick, make sure you copy and transfer over any authentication and 2FA things, as well as data for stuff that uses E2E (ex. signal, whastapp)