After digesting all of the information put forth, going back over ap notes, and looking at already proven layouts, I think I am finally ready to get some boards made! Any last minute quick changes that would behoove me to make, before boards are made, due to a mistake I've made? Thanks for all of the advice thus far.
Key design changes/additions
~Finalized board size and first enclosure. (PCB = 100mm x 50mm. Enclusure = Hammond 1590B)
~Decided to hold off on 2x2 array until I can get a single resistor design down
~Added Ground Plane and +15V Plane
~Removed Ref_Drive connections (not driving anything)
~Added alternate footprints for Vishay Resistors
~Postive/Negative net star points, both, on front side of PCB
Notes
~Paid close attention to balance and equal out the trace lengths of the most important connections, coming to/from LTZ and star points
~Streamlined component placement
~Attempted to get most efficient layout of resistors around LTZ without copying, verbatim, off another reference layout.
I'm excited to have this project come to fruition and join the LTZ reference club.