Like others have said just removing the bolt does not allow the gen to be removed. I use a bolt instead of the Tee nut because of clearance problems with my bumper. I also just use the Honda cover as it allows the upper strap to go thru the handle. That makes the gen as safe as any system I have used in the past.
I have suggested to TL they provide a pocket in the foreward corners to insert a wand to remind you just how far the unit sticks out front. I also have clearance lights on the front of the sides to let others know there is a extra lenght in front of the bumper at night. The wand also helps keep people from walking into the carrier in low light. I only carry a Honda 2000 right now but by the time I will need a AC I hope to have either another 2000 or a 3000. I think at some point TL will make a smaller carrier that will hold just a single 2000 and not stick out so much.
You can also use a upside down plastic tote for a cover. Just cut two thin slots in it for the lock bar to go thru.
About the locking hitch pin. A very good and cheap one can be made by drilling and tap a blind hole in a 5/8 bolt with a clearance on in one side of a nut.Insert a set screw that protrudes into the nut Once in place it isn't going to removed unless the thief has a hex wrench in his pocket. Not too much chance of that unless they have been peeking at your pin before hand.