IMHO,

For French PAX, the only option which makes sense is the following one :

- cut the "level miles" benefits for gold card (140 € is not enough, and I suppose it helps too much PAX to get the Plat Status, when these PAX do not fly in front class : the aim of AF is clerly to attract those passengers to Premium or Biz, or to get rid of them) ;

- maintain the benefits of the Plat card, because fee is higher and because I suppose those PAXes already fly Biz or Premium.