I think support for offline translation could be nice.
My phone has hundreds of gigs of free storage, and 12 GB of RAM, so it can run e.g. TranslateGemma 4B. Phones with more RAM could run the 12B version.
There are times when you don't have internet access, but still need to translate something.
If there was an option for downloading an LLM and keeping it as a backup then I'd have it enabled.