I don't need unionfs, right now, so if I can't get arround this issue in a short term, I'll just leave it outside for a second round.
About names for this whole project, I asked my wife some help and she came uo with a lot of ideas, from which one seems to have been to stay...
So it will be like:
White .... Linux (if there is not any one already -- I still have to check it more thoroughlly, though..) where the .... will be an animal, designating the function of the distribution.
So, right now, for the router/firewall project, it will be White Fox Linux.