Information about Spotter/Sniper might be also usefull.
Honestly, I've never really had any problems worth noting with the spotter system myself. However, I'm heavily into Alpha Strikes even if it puts units at risk. Surging gals into the open, murdering everything you can see, and making sure you end in cover if possible, with a couple of flanking gals that can counter fire.
Hit hard and fast enough, and the counter is usually tepid enough to just walk away with a couple of mild wounds, or even just deflections off your shields/armour. Even better if you're rolling a Tank (or in my case, a Gnomedisc) forwards.
I looked at your Airfield topic and I'm seeing ALL of your units clumped together in a big wad, which is a big nope. That's asking for a grenading.
Fan out with fireteams of 2-3 in different directions to cover the map faster. One girl forwards a few spaces, CTRL-Clicking to dash (in the dark, with Camo, if possible). Then a girl going a different direction. Gather as much intel as possible, then backup the girls in danger spots. Put all you can into making sure you end the turn with everything you spotted killed. Using a Sniper, they can also be way back near the transport and only need move if Line of Sight is inhibited.
Make it so that, if a grenade lands, it can only hit at most 2 girls. The AI does not like wasting explosives on single targets.
Don't use flares or incendiaries for light unless its something like a Fort mission or some other protect location/VIP type thingy.