Honestly I feel like an easy mode would rob people of the experience. The Souls series isn't about cheap deaths and frustrations. The developers use the difficulty as a tool to reward the player with a feeling of satisfaction that is hard to find anywhere else. The bleak and dreary world itself seems to put the player in a tense state, yet when you hear the sound of another undead (player) ringing one of the bells you can't help but smile because though you SEEM to be alone in this journey, you really are not. The invasions are just part of that atmosphere.
If someone wanted to play the game online for just the coop but doesn't like invasions, just be hollow.
BTW i'm really excited for Darks Souls 2. I'm playing the first one as I type this. I hope it doesn't deviate too much from what made the series successful.
