Maybe damage caused to friendly team members can be "reflected" back to the one who caused the damage?
For example, Tiger I is aiming between buildings in Sniper Mode. Just as he presses the trigger to hit the TS-5 that is entering his line of sight, a friendly AMX 13 75 zips in front of him, causing Tiger I to cause Friendly Fire to the zippy little guy. But instead of causing 220 damage to the AMX, Tiger I takes the damage instead.
Pros
- Accidental shots of the "man, you cut me off at the last minute" sort will still encourage fire safety during "corner scrum" peek-a-boom sessions
- Arty fire into groups of enemies + friendlies (e.g., facehugging) will be hazardous to the shooter, encouraging fire safety
- Careless shots (like the ones that guys take at the beginning of the match, accidentally hitting allies in the rear) will only punish the careless shooter
Cons
- May encourage trolls to cross your line of fire, in the hope that you *will* hit them
- Will actually exacerbate "blocking you just because I'm a jerk" situations, since you have absolutely no recourse. But even today, do you have any reasonable recourse when a friendly M4A3E2 decides to block your Matilda just because he wants to annoy you?
Perhaps this is a Friendly Fire system you have already considered and rejected. If so, then thanks for taking the time to read this post. I know there is no simple solution to keeping a game fun where trolling and toxicity rear their ugly heads, and I appreciate that you're working hard to keep this MMO accessible and fun.