Context: I like to translate song lyrics for fun and casual practice; two I've recently been listening to are 悪い人 by syudou and 悪人 by ive, and the similar titles got me wondering whether I should be translating the two terms differently.
I understand the differences in pronunciation and grammar— 悪{わる}い人{ひと} is an adjective modifying a noun, 悪人{あくにん} is a noun of its own. They both seem to have the same general meanings of "bad person", "villain", etc. What I'm curious about is, are they interchangeable, or is there any substantial difference in usage/nuance/connotation?
In English there's a big difference between calling someone a "bad person" (mundane, generalized, modifier of neutral "person") vs. a "villain" or "evildoer" (more dramatic / usually fictional, defines referent by their badness) ...
Do 悪{わる}い人{ひと} and 悪人{あくにん} have a similar distinction, anything that may make it more appropriate to pick one or the other based on context? Or is it just up to the writer's whim and syllable count?