Thanks guys, going to try to finish 3/4 bit by bit, I know the gameplay's a huge part of it, but story spoilers really dampen the experience for me.
And just thought of this too:
Something about the gas station clerk, he's one of the main bad guys or something.
Man, screw /v/... :/
I definitely wouldn't let those spoilers stop you from playing it. If I'm being honest, the whole murder mystery aspect of the story isn't why you would ever play the game; it's the character interactions and all the stuff in-between the main story that makes P4 great (and there's a whole lot of that stuff).
And while the spoilers you mentioned are pretty big, those specific sentences barely scratch the surface of the big picture. There's pleeenty more surprises to be found.