I personally think it's an amazing game, and you aren't far in so only the best is to come. I think Caribdis went with an extremely different approach to the art style than others but I like that as it stands out. after quickly re-looking at the game and skipping dialouge, I somewhat see what you mean but I would not say they seem 'sickly addicted' and it only really applies to the males slightly. Either way, I hope you enjoy the game as much or more (if that is even possible) than I did.
1) use it before. Edit: not really a major difference other than a scenes and maybe a heart.
2)It will give +1 heart to whoever you choose an item too (I believe). Edit: don't think there is major differences other than a heart.
This could be different for you if you haven't gotten the maxium hearts possible for everyone yet.
I'm glad you believe they improved. I will quickly check the maximum hearts for you, maxing out judie most for when you get to the entrance of the train station :D
Edit: as soon as you sit down on the train, you should be at around, (maximizing all points for Judie so it may fluctuate 2 hearts roughly)
Laura - 17
Judie - 20
Carla - 13
Rebecca - 10