Good or Evil?

Okay, so I am currently working on an RPG server and was wondering if I could ask a simple question about which you personally would enjoy more. Do you think that I should make it so that their isn't really a definitive evil side or do you think people will like it more clear cut these people are evil these people are good?

If you want to help with the server we are begining the building phase. You could also track the progress of the project by going to this link: http://www.planetminecraft.com/project/ ... er-builds/