Thank you for testing my maps, and more the detailed response.

didnt know the one tile canal could be an obstacle XD
And dirt expansion? Impressive
I used water plants and folktails after clearing the forest and flushing it clean
But I also grabbed water from sources placed in the ocean
Folktail options

Speaking of: This may be a fatal flaw, how should a player know!
I may have to at least add pictures of the underwater good sources
Also of the best place for a waterwheel
I am sorry if you had to rely only on island water alone but extra source is its its own hassle

Great idea to use badwater presure to give us an extra challenge!

Finished it on hard on cycle 80 something. Very interesting beginning. You have to micromanage a lot in the beginning because you don't have enough space for food so not so many beavers. The badwater pressure that has to be managed at every badtide so you don't flood was a pain but after i got sluices map was basically finished. Got rid of those horrible 1 tile water spaces that evaporated all my water and after that slowly expanded for more food and closed some badwater sources but fewer than i expected so i won't flood. In the end i didn't need much space cause i went for dirt for expansion.

Map is not very hard but is well designed to be complicated in the beginning. In the mid-late game it's just a waiting game to pile up resources.