I would love to see an X-3, but I know it wont happen, ever, and if it does itll be years down the line. Final Fantasy X is one of those more lasting FF games and it took a long time for Square to bother cashing in on 7 (note: there is nothing wrong with cashing in on your games as far as im concerned; games are profit firstly, entertainment secondly for large corporations).

A "Braska Jecht Auron" prequil wouldnt work very well.. People know whats going to happen, Auron said in the game that the world has barely changed in 10 years, and there isnt a lot to work on without making a HUGE game.. which would mean more background on Jecht (we dont know much about him apart from being Tidus' father and being a blitzball superstar).. then the actual pilgrimmage, and probably what happens after Braska is killed.. basically Auron dying, and travelling to Zanarkand while Yuna is brought to Besaid for the next 10 years.

It would send me to sleep, there would be no change. Most Final Fantasy games challange something, traditions of their world, thoughts, etc. In 7 you had Cloud challanging himself and being part of a rebellion, and in X you had the entire breakdown of a 1000 year old repressive religion and with X-2 you already had another threat to the world..

My own idea would be an adventure through pre-Yevon Spira. A random guy who travels the world in search of some sort of "truth" that would develop a storyline.. and it would give people an idea to see what the huge cities where like before they became ruins. You could throw in your mentions of other characters (Lenne, Shuyin..) but not concentrate on it. The only problem with this is there is no mention of it in the two previous games.. unless you are Yu Yevon himself.