Which is the best US airline?

Well I do research before I fly and I found that Southwest and Delta are the BEST safety wise, they rise way above the others. (Little to NO crashes, little to NO fatalities, Southwest best of 2 but both are amazing!) Also, Southwest is very cheap and they are one of the few airlines where you still get a free bag checked, snacks, and drinks. They also have a friendly staff and are mostly always generous! I believe (from the research once again) that those two are probably as best as you could get with United States Airlines...