This whole argument can be simply solved with adding damage dropoff at range - That way the beam shows but it may do 0 damage when distance is extreme
That and having people understand that if the fog suddenly dissipates when they get under a prop it's not supposed to be like that and abusing it is an exploit (we already told OTA/CPs not to do it from day 1).
I only shoot at cops that leave the base. It's cheap to shoot those on the walls. (I may shoot to miss to spook them)
This is something we're not applying at the moment because the map really doesn't offer much more, but shooting at the enemy's base and dying may end up in PK much like it did in WW3RP.
Though I'd reckon shooting those on the wall doesn't need to be reckless or anything, so I'd say the rule would go for the people who're chilling inside the base.