I hate when I'm leading my team, call in a Lightning Strike, a few of my teammates walk under it and I get booted. It's incredibly frustrating. I also think there should be a respawn delay, but not a wave delay like when the game released. A 3 to 5 second delay would be just fine. I hate killing someone and having them immediately respawn behind me.
For those times where you kill a teammate at the same time as an enemy, it shouldn't count as a team kill. There's times where I won't shoot because there's a teammate in the way and the enemy ends up killing us both.
a friend i play with almost daily gets a 20 sec respawn time if he team kills. i get kicked when i team kill.