Pete,
I was passed out for the night while this conversation was going on. I think you’ve got a great idea here and you know we’ve got your back as far as who thought of it first. I grew up with the Advent calendars and yeah we got busted for opening some early too. My wife has bought them every year for the past 15 years since my first daughter was born, it’s tradition.
One thought I have on the box design is to make a clear hinged lid with a simple seal to hold humidity. This way you can see the cigars through it for display purposes. The hinge and clasp can be on the sides of the box so it opens like a cabinet rather than from the top or bottom. The cigars can be wrapped in an opaque paper with the day and also a picture of the various items (i.e. 2 turtle doves, a bell, partridge, snowman, etc.) to give it the holiday feel.
You can have 2 rows of cigars with a half height divider between them near the foot of the cigars and one in front of the top row near the foot of the cigars to hold them up in place if the box on display vertically. This way when you open the lid the cigars won’t fall out and when you remove one you can see the top of the decorated paper on the cigar below it because of the half divider. This will keep the display looking full and festive longer. A stepped block at the bottom could keep the top of the cigars all at the same height.
I see you have a lot of good ideas already, just another to think about.