status is faster with AF. 40k miles is gold and ST E+, hence lounge access. You also get lounge access domestically with NW and upgrades (if you don't live in the US ). CO gets you domestic upgrades (+NW) and better Elite bonus, but you will need 75k for lounge access (international) and none domestic. If you fly AF anyway and book V-vlass (=100% miles) I would go with FB. OP is a good program too, it all depends on what you want and what is most important for you.
Redemption is about the same, AF gives Elites substantially more Y awards.