Unity aside, the Play Store has a standard method for shipping large assets (expansion files) but it's badly designed and I think won't work with this new schem

Unity aside, the Play Store has a standard method for shipping large assets (expansion files) but it's badly designed and I think won't work with this new scheme. There's maximum file size for APKs, and if you exceed that you have to put extra stuff in one or two (why only two?) expansion files. They recommend that these files be compressed, but they're explicitly Opaque Binary Blobs so the decompress/diff/recompress hack won't work. There is a standard format they recommend -- a disk image -- but it's so buggy on Android as to be unusable. (I finally saw some action on the bug tracker recently, so it might be fixed, or nearly fixed, in the latest version of Android.)