Here's what I do (with Terrans in TA on Tough in Huge+ map with 40-60 habitable worlds):
A-Trade for scouts.
B-Research and build Eyes of the Universe
C-Leave scouts around AI worlds for comprehensive coverage.
D-Create a screen of scouts around points of entry to your territory.
E-At the 2 year mark, establish comprehensive "Damn Grid" out scouts 2 sectors apart.
F-Be annoyed by a stupid amount of useless, easily destroyed damn ships in my ship-list and on my map.
What do you folks do? How do you penetrate the effin eff oh gee?
As a side note, is using CTRL-U after step F going to change anything in game? I'd rather cope with the Damn Grid than lose my sensor advantage. Do I lose it?