First, let me say that I think it's commendable that you're asking these questions and seeking this information.

Second, your questions are difficult to answer, because it depends.

Your first goal should be to come to know yourself and what you're looking for fully. You say you're not a sadist, but that can be a relative term. I wouldn't call myself a sadist, for instance, but I like the little whimper I get from my kitten when I push things past a certain point -- you might not get anything from something like that.

What you're looking for and what your style is will determine the type of submissive you look for. Curiously, they aren't all the same. The punishment/reward dynamic will be shaped by the two individuals involved.

For instance, you might consider caning a punishment, but for a submissive who really loves a good caning, it might have the opposite effect. Being put in a corner and told they're a disappointment might be a minor punishment for one submissive, but be devasting to another. You have to learn the individual's psychology and then tailor punishment both to them and the infraction.