1. Does anyone have 1st hand experience with non-full drain models ? From what I'm seeing the 150 gallon (4 BBL) models are all non-full drain for some reason.
Let's discuss a few things. Are you asking about pulling finished beer from the bottom of the cone? Are these fermenters 60 degree cones, or less steep? Dish bottom fermenters are a real pain to use.
I am quite sure you'll need fermenters with a racking port about midway to 2/3rd up the cone.
Will you be filtering and then carbonating in a bright tank?
Aside from those questions, I'd recommend that you find a job in a brewery doing cellar and packaging work. Even volunteer while you're planning and building your brewery because it'll most likely take a year to get it started. Everyone knows how to make wort, but it's fermentation and packaging where you make or lose money.