I totally disagree on Trevor by the way guys, he's only a questionable character if you view him as a third protagonist rather than, essentially, the central antagonist who you happen to play as 1/3 of the time. If you think of Trevor as "the devil on Michael's shoulder", his ridiculous over-the-top "edgelordness" makes perfect sense. He's an avatar of Michael's (the actual protagonist of GTA 5) psychological and ethical struggle and is thus somewhat two-dimensional on purpose. As is Franklin.
Unlike most games where the "best" ending is the one where you save the most people, The "good", "proper" and most narratively complete ending of GTA5 is the one where Trevor dies.
