Subject would be better if we wanted to posit a hypothetical subject that we can continue to discuss throughout a longer passage. This allows for continuity (we can talk about what options might be available to a subject after a previously considered matter) or restriction (we may have already qualified what sort of person would be a subject).
On it's own, without this use, it's meaningless ("what subject?").
One is used to make a statement that applies to everyone or practically everyone. In this case the themelves should be changed to oneself.
People would be preferred over persons.
You is often used informally, in a manner almost the opposite to how one is used - you take something that is general but you describe the effect upon the addressee in particular to make that point.