Sorry if im saying something already said. Didnt have the time to read through the thread.
My opinion:
1. Dont use respawns => no spawn killin
2. If u use'em, u need a game mode like Siege, where the offence is more than welcome to spawn kill defence. Defence is "supposed" to guard the smoke, not attack. (Thats one thing that doesnt fit real competitions. If u wanna win, u'll do what ever it takes)
3. If u play HH w/ respawns, u need a map that is big enough, so that guys in the smoke cant see the other teams spawn.
EDIT: ONLY way to avoid spawn killing and camping would be HH or Siege w/o spawns, right?