Thank you for your lovely and constructive feedback. 
It's super appreciated and I'm happy you enjoyed playing it, it makes me really happy to read that.
I loved to read that you want to see this as a bigger game, because that's the long term plan for me to make a bigger game like that.

All the critiques about the things that we didn't polish is super valid and the missing right collisions for the water is also one of them. 
After a long break in development, we just wanted to get this little game out, for it to see the light of day and not just end as an unfinished never released project. So we just fixed the biggest and most obvious problems and pushed it out as is.
In the next game I will keep in mind that we already solve those things better in an earlier stage and not run that long with placeholders.