There's also a difference between what the Scientists can build and what the Warriors allow them to build. At some point, the Scientists presumably researched different versions of the stealth inherited from the examples of the Nighthawk that Kerensky & co took with them, but upon being presented with the possible applications, they've generally received a firm Do No Want.
The Aerie is effectively the exception that proves the rule and that was probably only considered acceptable because some Warrior probably viewed at as not a "real" Battle Armor design.