Hi-Sec Auto Tracking (+1 range to auto turrets, missle turrets, pdd, and planetary fortress)
Building Armor (+2 armor to all buildings)
Neosteel Frame (Increase load size for bunker, planetary, and command center)
I've always never quite understood why, and was wondering why more terrans don't get these upgrades?
Hi-Sec Auto Tracking is 100/100, but can effectively shut down any Muta Harrass super hard, and can make 2 missle turrets completely deadly, especially with building armor.
Building Armor pretty much makes planetary invulnerable to any mass ling rush, and any muta harass.
Neosteel Frame pretty much allows mass bunker defense to be SUPER SUPER effective against both zerg and protoss, in combination w/ building armor this seems like a very very strong defense.
The only real reason I can see these upgrades not being used is simply because getting the +attack +armor upgrades are more important, but even when terrans are 3/3 they don't get these upgrades. I feel that the small investment into these upgrades can significantly alter terrans ability to push out without having to worry about any type of Muta harras, and their ability to crunch down on important offensive choke points.
What are your thoughts?