Although part of the problem is I'm not really writing anything at the moment ^^"
But the fic I want to write the most right now probably is an AU based on the Link Click live action's finale where ...
(putting this under a cut since spoilers ^^")
An AU where the antagonist succeeds in his goal of changing the past - saving his sister but at the cost of ~20 other lives.
And also while Cheng Xiaoshi was still in the past, and the sister in question learned what her brother had done for her.
The future that CXS knew is erased. The timeline changed in a way where CXS would have had no reason to go back so there is no longer a connecting point for him to return to. The things he'd experienced over half a year, and his fire-forged friendship with Lu Guang are now just a memory.
And as another fun consequence of the changing the past, it is no longer possible to dive back to any point before the moment the timeline changed (or maybe just that day/Guidu city - haven't decided yet)
I kind of wanted to write a story where it's CXS who's now stuck in the past (though not by choice) and has to renavigate his friendship with Lu Guang when he has a bunch of memories of their relationship that can't simply be re-experienced.
And because of how the powers work in the Link Click Live Action, I also want to do a potential role reversal with the duo where it's Lu Guang who dives, while Cheng Xiaoshi guides him.
Meanwhile the AU version of the antagonist who broke the timeline is not having a good time either. Sure he has his sister, but she's devastated by the events that led to this and their relationship is strained as a result (even though she knows this version of her brother didn't actually do anything). He's wants to help her and is also very interested in time travel as a way to help people make peace with the past.
So he and Cheng Xiaoshi would get entangled in this alternate timeline as well, and CXS also has to navigate this version of the man who played the false friend and manipulated him for six months :D
(Also toying with the idea of them becoming diving partners since Lu Guang is less enthusiastic about it)
I generally don't have a coherent plot for this AU, just a bunch of scattered scenes and ideas. But it's fun to think about