This is one of the things that I was sad to find out wasn't already easily doable mechanically. I'm not sure how hard it would be to integrate, but my thought was that the backend of linking a nondescript eyeball object to particular players and their door authorizations might take some real processing power and/or storage space to make happen. Plus updating existing doors to support the updated mechanic could be labor-intensive.
Of course, I have no idea, but if there were ever an overall pass on security systems and giving players more ability to crack them? I would hope that this might make the cut along with other changes.
Existing goodies like e-notes and locking briefcases could even have less (or more) expensive retinal variants. There's a lot of code-locked doors that would be far more interesting if the solution to opening them was to take a baka's eye out.