Are there clear advantages to having moving gantry move along the longer side? What I can see is I would not need as much tubing, so that a pro. however if I have the gantry move along the shorter side it should make for a much narrower table which will fit the space better.
Thanks
Jackson
It’s your machine, so you can do what you like. 
But the big advantage is Z error. Making the gantry smaller has a power of two impact on the Z rigidity. And it also means that if you have a bow or curve in the long side of the table, the gantry will ride on it, and follow that curve. So you will have less error in Z. If you have a smaller table (like 4’ on the long side), then it will probably be fine. That is as good as the 4’x8’ tables.