I dont really understand. you want more but less effective spotters? They have to be micromanaged more? You want spotters to be unable to spot surprise attacks.I like your idea about more units having spotter role/abilities. I would just add, I'd find it interesting to test a mode where spotters don't have an insane vision field around them, but have to use spotting ability, like decrease spotter vison around him, but increase spotting range and field diameter and duration for special spotter ability. Maybe that way 2 or 3 spotters wont see most of the map all the time, making more elements of surprise.
And can't you say radius instead of diameter? Can't see a unit that is 20 meters away because I got 38 Diameter spotting. Should spotters be unable to move while using the ability? How long should the duration be?
What use should the spotter have? the same just a little worse?
My head hurts trying to figure out if you want the spotters to have less total vision when ability is active, the same amount of vision or more than current binos.