Sooner or later, every airline will make certain passengers happy and sooner or later every airline will disappoint passengers.

I have found that most all airlines build at least 20-30 minutes of "fluff time" into their schedule and it is done to make their "on time" performance look better.

Most of us have little choice. In my case it is Delta or AA. No good option of JetBlue or any other carrier. Be thankful if you have more than 1-2 options and airports.