Unlock via PIN entry
Feature summary: Add optional PIN entry to Unlock or Unlock+Login.
As I have disk encryption with my full complex password, I'd be okay with pin entry being used for both Unlock and Login, but I'd prefer to have the option to Log In with my password, and unlock with my PIN.
Currently, if I sit down to my Windows machine, I can use password or PIN entry to login/unlock, and it means that my online account that it's connected to can be behind a much longer, randomized password; this I feel is a very nice balance between security and ease-of-use. Win10 does not have a way to disable pin from initial login and use a local password instead of the Live account pass, but an encrypted disk solves that issue to my satisfaction. This represents a small but significant reduction of friction for my windows machine over my linux machine.
How would you like it to work
I found this discussion on the wiki but it's from 2013 and doesn't link anywhere; it discusses adding a PAM module for PIN entry, using the PIN to decrypt the Password and run that through the pass auth.
It doesn't discuss the display side of things; it would be nice to simply plug in the pin and have it unlock when finished. UX is discussed on a superseded ScreenLock page; it talks about PIN entry and has screenshots of comparison systems and mockups, but the newer LockUnlockLogin page omits it entirely.
Relevant links, screenshots, screencasts etc.
I feel that the ScreenLock wiki page thoroughly discusses the UX with example screens and mocks.