I wondered for a little while about whether restoring my table would somehow lower its value. I now know this is a non-issue: there is no premium market for "original condition" foosball tables (unlike antique furniture, for instance). Once I got past this non-issue, my goal became to make the table look nice and play well. One advantage I had was that I was restoring a Bonzini and parts are readily available. Not sure about the availability of parts for old Rene Pierre's.
If I had that table (and I wish I did!) I would refinish the cabinet, polish the metal, repaint the men, redo the Gerflex (like you are) and play!
Good luck and keep us posted on your progress!