The ability to give a detector a radius of which they can detect stealth units (at the moment, sight = detect radius) would add for realism and use. For example, if a spy follows someone, they are probably close enough for the followed to see the spy if they look around. But if the spy keeps far enough away, even though they are within range of vision, they can manage to keep hidden, the further they go. But if they walk right behind the guy, breathing down the back of his neck, they can easily be detected.
Thus, enters the detector radius. A simple radius tag for detectors to let them have a separate radius for detection. How it works is simple: a stealth unit must be inside the detection radius to be detected, even if in the unit's sights. This makes it actually possible to avoid detection if very careful. Otherwise, the moment you see the detector unit, it's too late, they have already detected you. The detect radius can give you a short range of which you can get back out of the way, allowing you to remain undetected.
For example, if two counter-acting "spy-type" units are both stealth units and detectors (of each other), then if they walk too close, and see the opposing units, they can still hightail it out of there before they get close enough to be detected, and vice versa. The reverse makes the stealth unit almost helpless if it gets seen that early on.
Pros: Enhanced and more useful stealth/detector units
Cons: Besides implementation work, none
