That looks pretty good as all those commands apply to the cache that you have in your config.
You probably want to add --buffer-size 0 as part of that the cache backend doesn’t need any buffer at all which would help on memory.
Some android info here -> Rclone for Android (new app)
You can run Plex on that stuff assuming that you don’t transcode anything. Once you hit a transcode, things are going to crawl as there isn’t much power to support that.