"Master Tactiction"? You give me to much credit. Here is my fleet disposition when I end a game, so you can see what kind of warmongering lunatic I am, and what overwhelming force I use:
Total Fleet:
2 Cruisers
3 Frigates
4 Scouts
Attack Fleet (homeworld):
1 Cruiser
2 Frigates
2 Scouts
Attack Fleet (Long-Established colony)
1 Cruiser
2 Scouts
Attack Fleet (Colony):
1 Cruiser/2 scouts/1 frigate 1 scout/2 frigates
(Depends on defense)
Typically by the time enemy reinforcments arrive I have at least destroyed 1/2 of the population if not more and the spacedock. So if they DO get any kind of force there capable of repelling me I can retreat and repair while waiting for the AI to lower its guard again. Using this strategy I can typically take on 2 worlds and 1 colony without to much trouble. If I do so I leave myself without defenses of course...
Naturally I put on "I'm handling combat" 'cause I kick the AI's butt 1:1 with roughly equal forces.
Disrupter Screen? Why don't we buy a second spy and just take the tech by force...It would make a 25$ one-shot deal since we can retire the second spy in no time...Also I would be happy to have a 3rd scout that is made for special world-taking purposes.

I'm playing the turn tomorrow so have your plans up everyone.
Starfleet Head,
HSRTG