The neat thing about GC2 is the ship design ... you start with 3 different sizes of ship hulls -- tiny, small, cargo. Cargo is indecent for combat, since its the weakest of the bunch in terms of its hitpoints ... but I think it makes a *terrific* sensor platform. Why? It has way more space, so you can stick a LOT of sensors on it, and just a few sensor upgrades makes it even more valuable.
I find this very useful to monitor my territory, eliminating fog of war patches the AI likes to slip through. I generally make the transport-sized scoutship fast, with at least two of the fastest engines, so it can run from the enemy if needbe or run *to* an area if I need to monitor a new area. It also works wonders to help you recon enemy territory, find their starbases, etc.
I don't bother sticking any armor or weapons on, just engines and lots of sensors. This is terrific, especially early on when your only other options are small or tiny hulls, not much space for sensors or engines, and you can't see very far.