I agree with a lot of what you are saying but it depends on the game type too.
I play CTF a lot and in that game the only player who needs to stay alive is the flag carrier. Everyone else should be ready to lay down their life to attack or defend the flag carrier.
Having said that I do like to try and stay alive. I find their is nothing so annoying as coming back time after time to find the same player waiting for me and I like to think other feel the same so I like to remain alive and "in their face".
There are some strategic reasons for getting killed though. I have seen people in CTF games kill themselves (either be falling or by running into a fight with saber-off) so they can re-emerge, near the base, with full health/force and a little sheild. Imagine if I am chasing you towards my base where you are going to steal my flag/kill my flag carrier. My health and/or force is low and I cannot catch you up. However if I get killed I can be back at my base almost instantly with lots of health/force and potentially kick your butt.
As I say, it depends on the game and if its team based then I guess the team score takes precedence, isn't that how it should be?