However...I do plan on buying control arms that will allow me to add longer links in the future, if I'm so inclinded.
It would be rare for that to work. We generally tell folks with the Currie Short Arm that do the mid arm to just take the set and sell them intact. The only joints that work are the lowers moved up to be the ends of the 3 uppers and then you are left with 1 lower and 4 uppers to do something with IF you are working with something like the Currie or Savvy arms.
If you move to a "3 link" front with a single upper, I recommend the larger body for more durability but with the smaller 1" shank. You don't need the bending resistance of the larger shank so the smaller one works fine.