Taking a deep dive into Amethyst's caching. After 2 days of use, my user gets to 89MB of RAM for about 75,000 events in memory, including all the encrypted ones (DMs, lists, etc) that are larger.
The rest of the memory is occupied by images, videos, compiled classes, indexes, etc.
It's quite amazing that the phone can hold this many events and only then start to freak out and start these long pauses to find memory to delete.