I don't think blood should be added to the current anime. I think a different anime would be more appropriate, because suddenly changing something like this is a little nonsensical.
I'm all for blood in things like art, roleplays and stories, and even for anime and games (from a pokemon perspective or something) but because the anime is already established for what it is, adding blood would make no sense, be inconsistent, and suddenly change the target audience.
I add blood in my stories, because it makes sense to me. I don't think it's got anything to do with being "dark" because blood is a normal part of life, and it's more something that would happen as opposed to me being like "LOOK AT MY DARK MATURE STORY WITH LOTS OF BLOOODDDD!!!!!!!" because that would be silly. xD
Yes, I would be all for a new show with blood, although I get the feeling that if blood were incorporated, it wouldn't be as light-hearted. They'd probably use it to incorporate things like a more solid story aimed at an older audience with stronger consequences, even if pokemon can obviously die in the current anime. Kind of like blood in other anime, especially if it involved torture or exploding limbs or something. xD
Everyone who's still stuck here, Pe2k is Dead. It's sad, but it happened. Instead, we moved to...
Pe2k's spiritual successor! :D I'm Suicune's Fire there.