Portable Linux User Profiles

Aurochs

I'm working on a project, and I'd like to get some input. I'm striving to create Portable User accounts, for a larger project involving a new DE, that any person could throw on a USB drive take to a computer with appropriate installed packages, and sign in without hassle. 

Short Term Goal

Creating a Portable Linux Profile that will log a user into a Linux system with a USB drive, password. Initially this will give them a default desktop and they will have access to files stored on the USB drive with their Profile along with applications installed already on the machine, keeping the user off the device storage otherwise, unless the Profile originates from that machine.

Short Term Questions

Implementation of Security of Owners Device while a Portable ID is logged in?

Everything In Linux is a File. So what would be the best format to store all the user data to make a portable profile?

Can this be done with PAM and ACL?

There are other things I haven't considered yet as I'm just beggining the research and fesability stage of this program.

 

Long Term Goal

Create a Universal User Identification using an External Device as authenticator and storage for profiles, giving a person access to the exact same desktop everywhere (As long as the DE matches) and their files stored on the External Device or Cloud services.

I'm going to avoid asking about the Long Term issues for now.