The etiquette of a good team comrade

Some of the points I'm writing here cannot be solved modifying the game code, but with self moderation.
There are many, too many, occasions in which people of your own team don't help, or try to make life more difficult for other players! I can see that particularly in "Capture the flag", which is the modality I play the most.
Some of these bad behaviors are connected to the fact that, while the modality is divided in teams, the score is individual, with a leaderboard. I don't know the specific reason for that, but if it has to be that way... wouldn't it be better to have both a leaderboard and team points?
This way the capture the flag modality would have to be timed like "football", but I don't know... maybe a good solution would be to reset the team points every 10 minutes, and if you belong to the team that captured the flag the highest get a "progress" badge (that is also individual at the moment), or it could be a bonus for everyone in that team.

But now, let's talk about the behaviors:
-Sometimes players, when they get the flag, they don't take the point. The lurk around the base, or the run incessantly hiding in places, stopping the whole game.
If the same happened in basketball, and the man with the ball started running around the field avoiding his team mates and opponents, without making the damn goal, he would be disqualified for bad conduct.
Please: if you have the flag, put that damn flag where you should!

-Other times, a whole team starts making life impossible for another team, making a gang-assault against the other team, so that they don't even have the possibility to even get out from the spawning room to start playing! I think it's pointless and it ruins the game for everybody.
Imagine if you woke up and you couldn't start your day because your whole family started kicking you back inside everytime you try to get out. It's not good.
Simply put: there is no point in that, let everyone have fun.

-Another problem in capture the flag: everybody tries to "steal" each other's the flag in the same team. For example, while one is bringing the flag to the goal point, 4-5 players stand up doing nothing in the section the enemy's flag reappears. It doesn't make any sense. I would say: if the flag isn't there, don't enter!
I think that this could actually be solved changing the game: if the enemy flag is stolen and brought away from the flag room, then there could be a "subtle push" that pushes away every player from that room, so that it is still possible to enter inside while the flag isn't there, but at the same time it prevents people from getting stuck in the flag room.

This are a couple of cents... what's your take on this?