Here's a new FFX fanfiction that's actually really good:
https://www.fanfiction.net/s/10126561/1/Beyond-Reality -
Beyond Reality.
It's interesting, it actually provides a reason for Zanarkand being here, and though it's REALLY obvious who the Guardian of Zanarkand is (you could probably tell by the name alone if you're a big enough nerd) it's still pretty awesome.
Warning you though, Chapter 4 is PAINFUL for TidusxYuna lovers such as I (not in a bad way, but in a story way), but don't worry. The angst is cleared up and replaced with fluff in the next chapter. Also, one of the most badass things about Tidus in
The Return, the Responsible and the New War is present here if you've ever read that.