Of the criteria that are objective, there is difference among individuals (EG: we cannot say that everyone is equally tall). Of the criteria thats subjective, the evaluation differs between each individual (EG: beauty)
For both cases, objective and subjective criteria, not all people are equal.
Equality and "relative worth", or whatever you want to call it, aren't the same thing, and since the original premise was that no one is "better or worse" than another, not "different", the point remains that a definition is needed for "better" or "worse".
If we go down this path of definitions, we also need to define the term "person". Given the dehumanization that happens during war and terrorism, the person defining better has a major impact on the definition.