here are a couple of things I have been doing in my game that seem to work surprisingly well
1) AWAC/SWAC (Space Warning And Control, (yes I played SFB back pre doomsday) hulls , basicaly this is one of my early builds, take a Cargo hull, stick enough sensor on it to get range 10 sensor sweeps, and send it crawling to the boarder, a couple of them are usualy all I need to see deep into the neibors terriroty, often giving me several turns to react to anything the AI trys to pull because the AI seems to inevitably "stage" its fleets in my SWACs sensor range before they launch an attack.
Upgrades are usualy either speed or a couple of more sensors, and when I get medium hulls to build semi survivalbe SWACs I can convert them into Construction hulls for a quick beef up of border bases
2)I also tend to "Obsolete" the "Traider" and "Colony" ships as soon as I dont need them anymore, It seems that If I do need a Freighter to deal with replaceing a lost trade rout I'm better off going with a new hull anyway to take advantage of speed or range improvments
3) I have been useing thoes Big "Wings" to help me better spot a certan group of ships in the view mode, so I try and stick with certain things on certain kinds of ships so I know when Im looking at the map what I have handy in each area, and what should be scooted out of the danger zone( thus I know that if I see that big yello thing on the wing, thats a ship to keep out of combat)