"Friendly Blocks" would be the perfect way to stop the griefing from team members.
My idea is, to be able to chose a color that, for example a green player would chose and could only be destroyed by enemy players, or at least make it a lot harder to friendlies to destroy it.
Because, that's the only the only thing that is annoying me in the game right now.
One example of that is the bridge map, where 80% of the team is focused on destroying their side of the bridge , only making it harder for their team to cross it, leaving the enemy team with a big advantage;
So, with the bridge having the colors of the team on each side it makes it impossible, or at least A LOT harder and time consuming to destroy the (green or blue) blocks, depending of the team.
I really hope this suggestion gets through, because the game is almost unplayable without anything like this.