Yes, the violence is a bit bloodless and passionless, usually. And the drop-ins of non-look-alike doubles all diminishes the violence portrayed.
You're right; it's not graphic. But you also have to remember how people treated the violence as well. Kirk was always concerned for his crew when they died. No one was just collateral damage. He tried to find out what caused their death. He was worried that his decisions would lead to more deaths. You didn't see the red shirts die unless they were incinerated, we heard about them dying. Like in "Galileo Seven," "The Man Trap," etc.
Yea, but, also, there were some episodes that ended with hilarity that seemed really out of place considering the death that had just occurred (Though, admittedly, if you weren't offended by how easily they moved on and forgot the deaths, the levity did end the episode on a high and keep it from getting you down)
One Day I hope to be the Man my Cat thinks I am
Where are we going? And why are we in this Handbasket?