Looks awesome! I'm a bit worried about how #75 can be solved with the water to the top connecting directly to the water to the right, but maybe that was going to be difficult either way.

It's ultimately up to you how you want to solve it, I'm just fretting (perhaps needlessly) about creating some sort of situation that's impossible to solve for 75. This is how I'd imagine the land would look in those three tiles:
there would only need to be a little piece of a waterfall in the corner of your tile, but feel free to ignore if you think it can be solved without it.