I look at respawn a consequence of dying. If you don't want to wait then don't die. It makes you play smarter and less suicide missions. With instant respawn you can do whatever you want and know you will be back instantly. Plus I like the ability to taunt after I kill.
I'm not opposed to a shorter respawn time. 30 sec is a bit much. Take it down to 20 or 15 sec. Just a suggestion. I'll continue to play regardless of respawn time.