1. I don't think so...it's not worth it ,and as you said it ruin the flow of the game. the only time that I reload for chest it was with Bellegar barrels (and still it was really crappy items).
2. I think it only depends on the area level range +-.
I skipped (accidently)on the Ice map and clear other places...and then I've realized that I need to go to the Ice map...I was 4 levels ahead and the items was 4 level lower
