File (Field) Paths is stable. 8.x-1.0 is the first stable release since the Drupal 7 one (long may it live), and it does what it has always done: sorts and renames your uploads with token patterns, so you get a filesystem you can read.
If you've been holding off while it sat in RC, you don't need to. It has 215 automated tests and 1287 assertions where beta8 had 21 tests, a safer default for where uploads wait, and a plan for what comes next. It's under active maintenance again.
Core file fields let you choose a directory, and that setting takes tokens. Drupal ships [date:custom:Y]-[date:custom:m] as the default. What it can't take is a token about the entity you're attaching the file to, because at the moment the file is saved those values don't exist yet. The file name isn't touched at all.