The problem with stories like this-- and the original Patrick O'Brian slash AU conceit that kicked off the Temeraire books-- is that they are tantalizing beginnings, all zoomy with potential. I end up wanting to read the rest of the story. I am greedy.
Also, am in the grips of this exact problem with my current fic project. I wrote a few thousand words of self-contained story that was a really great setup. And then I wanted to know what happened afterwards, because awesome as that setup is, I wanted even more to watch what happens with Giles & Buffy afterward, when they have to cope with the consequences. Slog slog. Plot plot. Write write. See you in a couple of months, when I will emerge with a 40K-ish medium-sized fic that will keep about a hundred people on AO3 entertained for a couple of hours.
I really hope the exploration of What Happens Next will be worth the work. Sometimes potential and possibility are more fun than the collapse of the multiple universes into a single reality-state.