How do you use keepassdx in the wild? Do you have everything setup to rarely ever need keypass? Or to rarely need to the type the passphrase? Do you use an external device, like a yubikey?
Lets say the camera you don't notice is the one that can analyze your finger movements. But maybe that can be made harder to analyze.
Already have device pin scrambled, privacy screen, and plan to backup the keyfile to different locations than the password database. Have a dummy password database to try your suggestions with.
Heres the discussion on how long your passphrase should be. Don't want to split the thread here.
https://discuss.grapheneos.org/d/22857-optimal-length-and-structure-for-passwords