The issue with this however is a larger air intake would need some kind of mesh cover or grill to prevent burning coals and logs falling through and starting unintentional fires.....
Funny - I was just talking to my wife about this subject over the weekend, because there is indeed the possibility of embers rolling out of the vent with such a large opening.
I don't really worry about it with my setup because I mounted my pit over a thick bed of landscape rocks. However, it might be more of an issue if you had your pit on a wooden deck or something like that.
My conclusion was that even the large vent opening provides a narrow barrier at the bottom of the firebox door which would stop most objects from free-falling out of the firebox, as compared to leaving the factory door open, which most Wichita owners have accepted as normal operating procedure. An open door is definitely more dangerous than a door with a narrow barrier at the bottom.
Since I have been using my makeshift firebox cover I haven't had any issues with embers falling out. On my last cook, I noted how easy it has become to manage my fire - something I don't even fret over anymore. I just throw logs in the firebox and go back to whatever else I was doing. I keep a Maverick thermometer in the house so I can monitor when the pit temp starts to decrease, and then I throw another log in and walk away. Easy as it gets.
Here is my lighting sequence. I used a small stack of splits with the log lighter to ignite the fire:
Once lit, I close the lid and I'm done. No coals, no fanning, nothing. I just wait for the pit to reach 225 degrees. Here you can see the logs burning cleanly with the lid closed, and zero coals - the fire has only been going for about 10 minutes with the log lighter before turning off the gas and shutting the lid. The debris on the bottom of the firebox is the wadded up newspaper I used to ignite the log lighter. Note: I always remove my log lighter and store it after I light the fire, which is why it is not visible in this photo.
Here is the smoke from the smokestack right after closing the lid for the first time. No billowing smoke, and good pressure because the firebox is not venting out the back side. You can kind of see the gauge is sitting at around 100 degrees in this shot - just getting warmed up.