Thanks for everyone's replies so far.

Nationality is Canadian. I'd be checking one bag. The flights through Mexico involve an overnight stopover - so that's what worries me in terms of safety. I'd have to find a hotel for the night, near the airport, and find a safe legit taxi to take to the hotel. I'd also presumably have to go through customs for Mexico each way and I don't know what that involves - whether they pick Canadians at random for secondary inspections, fingerprinting, personal searches, etc.

I'm not so concerned with the length of line ups for customs/TSA as what happens when I get to the front of the line. In particular I want to avoid body scanners, fingerprinting, and other invasive searches.

Flight delays are a lesser concern - unless the delays are excessive.