Thanks for the critique! I don't see any issues here I expect to be fixed for the Content or Normal modes (except for Long Gui which has already been fixed), but it's good information all the same. Thanks!
As for some specifics, let me chime in in no particular order and DK can comment on things as well...
You're complaining that the earliest bosses in the game are too easy. Think about that for a second. I've seen players lose to the Hammer Bros and nearly lose to Croco.
(as for Croco 2, remember that unlike most fights, you can't use items. As a result, it has to be easier or else less skilled players would simply get stuck there)
As the primary reward for finding every hidden chest, it's deliberately overpowered here. Keep in mind this is only Normal mode, so some things are deliberately OP for the player to abuse.
This was a deliberate change compared to v8: Lazy Shell is no longer the end all for armor. It'll help you survive attacks, but there's definitely better armor out there. It's best used for the earlier superbosses.
I agree... I think they should have been limited for the FF boss rush too.