I would suggest to be a bit more deliberate about choice of preferred airline/alliance/hotel chain (based on what works for you), and then make your credit card choices appropriately.

So, for instance, if Hilton works for you as a good hotel chain to earn/spend points, then focus on appropriate cards (Citi HHonors Visa, Citi HHonors Reserve, Amex HHonors, Amex HHonors Surpass). You can keep 1 or 2 of them as "core" cards based on what is of value to you, and get the others for the sign-up bonus and cancel after a year.

Many will tell you that the "value" of an HHonors point (derived from ease of earning and cost of spending) is less than that of other hotel chains such as Hyatt, or Marriott.

So you have to read about how value is computed, and then make the decision for yourself based on your earning/spending preferences.

Similarly on the airline side - pick American/OneWorld, United/Star, or Delta/Skyteam - and then funnel your travel to that airline/alliance to maximize your ability to hit and enjoy elite status. And pick credit cards then that match the airline of interest. I prefer United/Star and so my cards tend to be CSP, Inks, Freedom (Chase cards that yield Ultimate Rewards points that can be transferred 1:1 to United) as well as Chase United cards. Again, keep some, and get the others for the sign-up bonus and then cancel/downgrade after a year (many of them come with no annual fee for the first year).

Cards such as the SPG and Amex cards give you earning currency that can be transferred to many airlines/hotels, so these can be used to supplement your earning potential.

So the critical thing is to identify your airline and hotel chain of interest. The rest will follow.