Thank you for your kind comment and feedback!
I'm sorry to say that, but right now I have no plans for further updating the game. This is partially because I feel it's complete (previous updates were all things I had planned for the original release, which didn't make it in back then because of time constraints of IfComp), and partially because the game grew so big Twine editor cannot handle it any more. You noticed how long the code is - this is also because it's poorly optimised (I learned many functions as I worked on the game, and didn't learn some useful stuff until later, which would help clean and optimise the code). Right now, adding more stuff to the game would basically require rewriting and improving everything, and I rather make new games based on what I learned from this one. I don't categoricallty exclude the posibility of making a "remaster" of Archipelago one day, and then I'll certainly add new content, but this is all preliminary ideas now.
As for Coral City: it is intended to be difficult, as it's an optional dungeon, and the only puzzle-like one. That's why there is an autosave before you enter and no autosaves in the dungeon - so that you can easily reload if you get stuck. A hint for exploring the City, if you want to return there: pay attention to how long the current carries you each time. It helps figure out where you end up. For full solution, there is this excellent map a player made a while back, which explains everything: https://intfiction.org/t/trizbort-or-other-maps-for-ifcomp-2021/53008/10
Cheers,
Agat