Cloaking
That's right, I said cloaking.
Builders would be able to toggle cloak much like they are able to toggle structure protection with designated builder.
Defcom is needed for cloaking. The reactor, defcom and telenodes are not cloakable. Cloaked buildings do not show up on alien radar or visual contact. To prevent hiding an entire base, cloaking costs 2bps, but the bps is returned when the building is uncloaked or destroyed/deconned - this would be a useful way to spend those last 6bps when your base is done.
Please dont flame, I put a bit of thought into this idea which is more then I can say for a lot of the ideas here.