Do we know what's in every chest? Or have it mapped out somewhere? My friend wants to run this game, but he wants to know what chests to grab and what other chests not to grab.

eh i dont actually know if its docemented anywhere. Items are documented 100% with locations but consumble stuff probbly not. Anyways i would advice to simply run game 1 time just to find out what is more comfy to you. gl on the runs, hope i gonna do them too XD