is reason alone valid knowledge, or do we always need evidence grounded in science to act .

[gnostic]

a creed is a set of aims or beliefs that guide people, and unify their stance.

But creed is largely concern with belief regarding to religion and faith.

perhaps your creed among others is that we should only live our lives according to empirical evidence, objectivity that is testable, and falsifiable, and is subject to peer review. That would be your belief and your conviction.

Creed has nothing to do with science, and vice versa.

What you are saying is wrong about science, it has nothing to with belief and faith (conviction).

Empirical evidences are the opposite or antithesis to faith.

If you have evidences, then it is no longer "faith". Faith is about accepting belief without evidences.