New Rating System

I am planning to do away with the 5-star rating system, and need your help to decide what to use instead. I was thinking about simply using the Like system, but wasn't sure if it's a good idea to do away with the ability to rate something as poor.

Ideally I could make a "Thumbs Up / Thumbs Down" system, but the closest I could make would add and subtract from one value, so if 2 people voted up, and one down, the displayed value would be 1.

Let me know what you think of my ideas, and feel free to submit your own. Please don't question me as to why I'm removing the 5-star widget, as it is not up for discussion.