Poor wording on the "good many", I'll grant. However these few years have seen a great deal of improvement in the general quality of animation.
Accepting that as a tangential point, consider this: You say that the two broken fingers in Shigurui (again, an awesome scene) convey more than Elfen Lied's blood and gore, but you need to ask exactly what it is the violence is meant to convey.
In Shigurui the sheer carnival of carnage that Elfen Lied uses simply wouldn't be appropriate. However by the same token Shigurui's two broken fingers would be largely meaningless in Elfen Lied; the person would go to the hospital, or their high tech medical facility, and get it patched right up. Painful and unpleasant, but nothing compared to what some of these characters have been through.
The damage being dealt to these characters needs to be on a level where it is permanently debilitating, beyond any of our medical science to repair. Similarly the body counts needs to be high just to justify the expense that obviously goes into containing and studying these creatures. What is more, it's important that the violence appear quite casual, because this is a part of Lucie's character. She doesn't really take the time to torture slowly, she just swats people aside like bugs, because that is what they are to her.
My other thoughts on the somewhat exaggerated violence of Elfen Lied go back to my comments about the harem / horror mash up. The violence is horror violence, not drama violence. Elfen Lied deliberately borrows the tropes and visual effects of slasher flicks so as to emphasise just how out of their depth the characters really are.