How do you earn your miles?
- Do you fly a lot for work or on paid tickets to earn miles?
- Do you earn points in a credit card program that lets you transfer to hotel or airline programs?
- Do you use an airline co-branded credit card that earns miles for your every day spending?
- Do you do the 'app-o-ramas' or 'churns' where you are getting many different credit cards for the large sign up bonuses, then cancel the cards and reapply for more?
The answer to those would help. There really isn't any one FF program that is the best. It will all depend on what you want. A lot of people say Delta is the worst for redemptions, but if you can get a 50% transfer bonus from AMEX and you want to go to Australia or the South Pacific then it's extremely valuable.
It sounds like you get most of your miles from credit cards. Cards like the Chase Sapphire Preferred or American Express membership rewards cards are great for that. If that's the case, then there's no harm in joining any and all FF programs.
As a general rule, don't transfer your points out of AMEX (or other CC programs) until you are ready to redeem. Keep the points there, where they are flexible and transferable to multiple programs. When you want to take a trip, search for a cheap award on all of the airlines and when you find one then transfer the points to book the ticket.
A specific FF program could be considered the worst program that is rapidly losing value. But if it happens to have the lowest cost award to the destination you want to travel to, then I would argue that it is actually the
best program for you
at that moment in time. FF programs are very subjective, and the strength/weakness of them is totally dependent on individual situations and needs.
The best approach, if it is feasible for your lifestyle, would be to try to diversify and earn points in a couple different programs. That way there's bound to be some availability for where you want to go between the multiple accounts. Keeping credit cards with the ability to transfer points directly into FF programs is great way to do this.
Now that being said, if most of your miles are earned in a specific airline by taking flights or using a specific airline's credit card it's a different story. If you are earning points in only one airline, and locked into it then you can look at it as a whole to see if it is generally good or bad.