Maybe if the killing blow was made with a critical strike it would show the most blood or gore.
Man that made me think of a Barb critting something with a nice 2h maul, blood EVERYWHERE, muscle and bone churned into wallpaper. In the gameplay videos the blood seems good, but maybe a little less would be perfect. The new Monk screenshots seemed a little over the top though.
I agree that every single monster shouldn't have an explosion of blood and guts. Yall are right that it does take away from letting our imagination create a horrendous scene of death and gore. As Hans stated before, I think a critical hit should lead to the body exploding.
I love lots of blood in game a game - as said earlier it gives you that guilty pleasure and satisfaction that you did something. But too much is too much sometimes, if we had ridiculous pools of blood all constantly it would loose all of its affect. A varying level keeps the gore in context, just like how Siegebreaker beast ripping off the Bar's head was like OMFG! If it was constant we'd say Meh.
As for if blizzard will make render the blood further? When you compare it to the beautiful desert scenery, it seems incomplete, but it may just be this particular screenshot.