Ryan,
I own an MFT 1080 and an MFT 800 and plan to add a 3rd - I have not decided which size to buy next. Many of the custom built MFTs on FOG are larger than the 1080 in size, and presumably well fit the needs of their constructor owners. But before plunging into making your own MFT variant, particularly an extra large one, you might also benefit from checking through the MFT related posts by Jerry Work. I recall that when he wrote his excellent manual on the MFT that he described how and why he built one with a very large top for use in furniture construction. But later, he posted that he had dismantled that large MFT and had gone back to use of multiple MFT 1080s due to the ability to reconfigure them according to the needs of various projects. He is a professional furniture designer and maker and makes some rather complicated pieces requiring much precision in layout and machining of the components. If I were to make a custom MFT for my own use, I would strongly consider mating it to one of the roll-about hydraulic lift hand trucks. Doing so would enable its use to lift and transport heavy items (once lifted a short distance onto the table), to adjust the height of the workpiece to minimize your motion and strain on your back when working on a project, including applying a finish, facilitate transport of heavy sheet materials (adjust to truck bed height, pull on sheet, transport, raise or lower to assist unloading), enable use as a perfect height extension to any other work table or jointer, planer or table saw, and enable you to roll it against a wall for storage when not in use. (Gee, I think I just sold one to myself! But still, I do not see a need to build my own MFT to gain all these additional functions. All that I would need to do is buy one of the small lift carts from Harbor Freight or another vendor and secure a complete MFT 1080 to the top of that lift cart. Then if I needed another MFT 1080, I could dismount it and couple it to my other 1080.)
Dave R.