What is the hardware made of? Is everything either galvanized or stainless steel? That is a must for outdoors in my climate.
I see that you have focused on handling cold winters, but wonder how extreme heat and humidity of Florida summers will impact it. The width of the combs appears more like what I saw doing three cut outs this summer. However, I wonder why we keep building the comb to be horizontal when bees build it to be vertical.
The tipping of frames is still a concern for me, especially when building up a hive. Have you considered a hinge style that won't cause so much rotation? I was in build up mode this year and constantly in the hives to split them out, move brood from strong hive to newer hive, ensure queen rearing hives had plenty of stores, etc.
How will you provide useful boxes for queen rearing and nuc size building? I can see starting a hive in one box, but around here I don't like to have empty boxes that can't be defended and it looks like multiple boxes are needed to put a feeder on. Too many palmetto bug, german roaches, etc. like to call them home. The thought of the nasty bacterial and disease they carry getting into my honey hives is not a pleasant one.
How are you overcoming the problems that some people see where bees won't cross a queen excluder, which looks like it may be an issue with the slits as passage between boxes. How much space is needed between hives?
Even quality exterior plywood concerns me in this environment. Constant rain, heat, and humidity usually destroy it rather quickly. What type of rating does it have for en environment like mine where it will be exposed to the elements, not covered by vinyl to protect it. Paint helps some, not not as much as one might think. Having painted surfaces stacked on each other will glue them together worse than propolis in the summer.
These don't look like they will stack well compared to langs on a pallet, so commercial beeks are off the menu. Your 3 hive backyard, keep it aesthetic looking crowd is probably your best target group.