I've seen this topic almost beaten to death (quite literally), but one thing I didn't see is something as simple as before you die having the ability to crawl around wounded and then die. Like once shot you will die and you cannot be revived. You can either opt to respawn and skip it or crawl around wounded and bleeding on the battlefield for 30 seconds or something. Just seeing the aftermath of the battle in the movie Gettysburg sets the horrific tone of battle. Seeing men crawling around the battlefield wounded. Writhing in pain. I'm sure it would be interesting to have a few different actions with wounded players who do opt to take the 30-seconds or so before respawn to crawl around adding to the ambient environment.
I dunno, just late night thinking out loud.
Ugly