I'd love to visit wherever you decide to build your life size Autobot City,
and it would make an awesome theme park
What I wouldn't give to have had an life size SCALE Autobot City as a kid! What would I pay for it now? Probably a fair bit, as as good as Metroplex was, he was not the compelte Autobot City.
When I first read your thread, I thought ambitious yes, but doable. Production of boxes, well its main cost is the art and design - print one, print a thousand, you can just keep printing them. But given that you want to produce actual toys as well...... this seems to me to be in direct competition with Hasbro. I'm not sure they would agree to license at all.
I think the reason Fansproject and other third party manufacturers can get away with what they do is that they're small, but if you're thinking 50 issues of a comic that's a BIG production there. Before you start hiring toys and designers, you'd want to get a license in writing before investing too much work.
It would be a shame for these very GREAT ideas to go to waste. If you wanted to make a toy that big, for example, you could go generic like the Autobot Ark playset, that didn't directly infringe Hasbro/Takara's intellectual property. There's a fine tradition of third party products (across many toy lines, think of the generic Lego type products you can still interface with actual lego) that are designed to be compatible with another toyline, but not in direct competition.