I honestly cannot ever see this as being a worth-while exercise.
For starters, you've got a load of licensing issues. Then you have the overheads of running a server - actually at least one, possibly several (though they could be virtual) since to run AD, you actually have to put in place a whole Microsoft stack.
Why not do as many now are, use Dropbox or similar to keep your active documents synch'd to the cloud - they will appear on any machine that has been set up. Set up each machine with the same user names and passwords and configuration, it would still be much quicker to set up than setting up AD then setting up Group Policy then setting up users.
No, set up each machine the same way - I do this with a crib sheet for our family computers - you could also write a script to help (I do this on Linux but it's not so easy on Windows). Have the same user id's and passwords on each and use Dropbox and similar cloud tools to keep data synchonised. If you don't want data in the cloud, use some local synch tool such as SyncBack SE.