I researched the 30A twist-lock solution (popular with RVs), SmartPlug inlet and connector (safety optimized for RV and marine), and went with the simpler approach I learned here: 15A plug on the back corner plastic with wire threaded in through the air baffle.
What works for me: my AC needs are simple - built-in shore power charger/supply, occasional power tools or fan. Maybe someday a small microwave, but my inverter is only 1200W, so an upgrade would be necessary anyway.
What I'd do differently:
1) I drove away with the cord plugged in. Fortunately it pulled right out, which may have been a worse scenario had it been twist-locked. I remedied the situation by installing a bright red AC LED on my dash, so even in bright sunlight I can see that I'm plugged in.
2) I park my van head-in to my driveway, where I often work (or sleep or read) inside of it on shore power, as it's an extension of my man-cave (garage). This results in using a long extension cord plugged in where miscreants can (and do) mess with it from the sidewalk. Someday I will add another plug to the front bumper which will allow me a short extension cord from an outside outlet that people would trip my security perimeter (lights, camera) to mess with.
So, both your physical and electrical use cases will drive your decision.
P.S. General AC electrical rule of thumb is 15A outlets are to use 14 AWG wiring, 20A outlets are to use 12 AWG. I wired my interior with 12 AWG stranded, which is likely overkill, but I used 15A outlets and plugs because they are far cheaper and more readily available.