Did you just call FF games III-XI "shoddy ground" or is it the Jdorama XIII and XIV that you're referring to?
XI was mainly built around the systems invented in FF III and it has lasted the test of time for over 10 years FYI.
In similiar fashion I think completely new MMOs could be based on X's Sphere grid character progression, XII's party based gameplay or IX's weapon and equipement heavy game design.