Warn before the screen gets locked
I often leave the phone unlocked while I do something else: drink tea, start a program via ssh, etc., with the intention of coming back to the phone in a moment.
Then phosh locks the screen and I have to type the password again, which is mildly annoying.
This minor annoyance has been successfully solved on KDE, where the display gradually darkens before the lock screen kicks in, and the process is cancelled on any user interaction. Moreover, the first few seconds after the lock screen is displayed, the screen is not actually locked (any interaction unlocks it). This is useful to me because I rarely notice the darkening.
Those serve as a warning: "if you don't touch the device now, you'll have to type your entire password soon."
I think Phosh could adopt the idea. At least the darkening, but perhaps also a third state that makes the screen change enough that it's difficult to miss – but unlike KDE, which wouldn't lie about the display being locked.