WOW. Sometimes people ask big questions, and then wonder why all their answers look like the old story about having 4 blind guys each feeling up an elephant to figure out what it is...
First and foremost, you need to let your strains tell you what to build. You gonna run a shitload for variety? Or, run only one for productivity? Or- and this is my suggestion- pick a few reasonably closely related strains that are ALL either indicas or sativas. Then, use the strain's characteristics to determine your warehouse layout.
I like the idea of four flowering rooms. This way, you can switch them out on a schedule 1/4 the length of the overall bloom phase (which is how long?) That helps to drive more consistent results and helps create a much more manageable workflow.
To fill four flowering rooms, you're gonna need a lot more than 1/4 of their total square footage in veg. Unless you do
sea of green, which will very quickly exceed your plant count (why 243?), you will need to grow them larger before putting them in bloom in order to get the productivity you want.
I have been advocating an interval approach, which in one way or another will be about the only way you'll be able to handle this size operation. Setting things up from the beginning to stage through every few weeks (two? eight week total bloom divided by four bloom rooms?) will give you huge advantages in terms of space utilization, consistency of results and process management. At this level, you're not building a growroom or four, you're building a factory and it only makes sense to approach it that way.
What's your budget? Is the cash on hand for equipment, consumables and utilities unlimited, or are there some constraints? What is the level of experience in your growing group, and just as important, are you all on the same page philosophically? If some have one idea how to proceed and others have different ideas, I guarantee you'll get nowhere fast, but broke.
Have you thought about building out part of your setup on a small scale and then sizing things up as you go, to gain experience and keep control of things? If so, what's the size of your scale? You want to start with 1/4 size environments?
What about the mechanicals? Not only is basic electricity supply and security an issue, but how are you going to light and cool such an expanse? What about runoff? Please don't tell us you're gonna just piss all those nutes down the drain!
Clearly, you're onto something with UC systems, but what if I told you I could build systems of similar performance for 25% of their cost, with components readily available locally- so that if something goes wrong, you can fix it immediately, instead of waiting for shipping?
What about pathogen management? What happens when the thrips or powdery mildew show up? What kind of pest management and outbreak eradication strategies will you have in place?
How about configurability? UC systems are great to set up- once. To reconfigure them is a BITCH. I think the design of your grow setup needs to emphasize flexibility, to be able to incorporate what you learn along the way and take advantage of those lessons.
Are you looking for... well, what? Maximum output? Maximum quality? What exactly are your ultimate goals and how does each component of your process fit into that vision? If you can't say how each and every damned fitting and foliar spray answers that question, you're already headed the wrong way...
The bottom line is this; you need someone who has done this before, at the level you're playing at, to be in charge of the mission, from NOW. Flying someone up once its all running great sounds fine, but it'll never happen unless someone is in charge of the setup from design onwards. You're not growing in your college dorm closet anymore, it's time to call in the professionals. The best are not cheap, but you stand to make plenty of money to pay for us- conversely, you can find yourselves deep in the hole overnight if you overlook something.
