Over the years I have repeatedly told my friends, "if you can get a direct flight into Cancun, as opposed to a stop over and plane change anywhere, you are better off".. First off, there is no chance of Ice Storms in Cancun nor missed connections in Houston or Dallas. The feared Bag drag in not REALLY and in almost all cases it will get you to Cozumel faster than any plane change scenario, with little risk.
Whether you pick Atlanta, DFW, or Houston for a change of planes you are always going to have risks of ice storms, thunder storms, etc. I know from lots of personal experience. Indeed for many years while my mother in law was ailing, my then wife and kids live in SoCal. I can't tell you the number of times I was screwed by aircraft change in Houston. IF it wasn't the weather it was Immigration or airline stupidity. All the while Alaska Airlines had non stop from LAX to Cancun. I learned my lesson.
Again, a non stop flight into Cancun is always less risky than a plane change to Cozumel, plus you will likely save some cash. Now my kids live near Houston and even then I often fly into Cancun rather than Cozumel.
Dave Dillehay
Aldora Divers