Thanks! My team member and myself very much appreciate your comment and criticisms!
Yeah, there was a healing system intended to be implemented, which is what the statues and watermelons were for. The healing system was originally supposed to contribute to the lore in a funny manner where a useless game item can be sacrificed to restore health, but due to time constraints and other subjects taking up our time, we weren't able to have enough time and energy to fully polish that part of the game.
The NPCs also originally had their own part to play in the world and story, but the limitations I've mentioned was an obstacle. So there was no choice but to simply just push out the project for the submission before the deadline.
I would also say that both of us sort of over-estimated ourselves and made the scope a little bit too big, which caused a lot of the missing game mechanics and problems you have mentioned, we're mostly proud of what it is currently nonetheless. We wish to improve (or even overhaul/remake) it further, but the chances of it happening I'm uncertain of.
Thanks again for playing our game and commenting!