More random stuff about 10 that I found annoying and/or bad from the top of my head:
The underwater breathing. Or do they hold their breath?
The physics underwater.
Yes, this is fantasy, but we are expected to accept it at face value. If you can accept it, fine, but I reserve my rights to call bullshit on it.
A blitzball as a weapon. Lulu's stuffed toys as weapons. I facepalmed at this. I think I hurt my face.
Tidus' blatant stupidity as a plot device. And also the fact that Tidus is the protagonist. Yuna, Auron or even Jecht would be better choices. I get the first-person-point-of-view narration mode they're going for, still those 3 persons I mentioned are far better protagonist choices. That, or they could have made Tidus a more relatable, and far less annoying person. Who relates to a sport-star crybaby idiot from a futuristic society.
Recycled dialogue every 20 minutes or so. (Sin is Jecht... This is my story... Sin is bad... Zanarkand... blah, blah, blah). This isn't necessarily bad, but imo annoyingly executed.
Stupid hairdos. Wakka... Seymour...
Yuna's resolve to confront Seymour alone was stupid. Not brave, just stupid. In both writing and resolve. She even had at least 2 perfect chances to send him after they killed him. Why didn't she?
The Al Bhed kidnapping summoners. Ok, so they are against summoners sacrificing themselves for the greater good, yet no problem killing of guardians in the process. Rikku's brother had no problem sending a death tank after the party his sister was in. "Hey father, I rescued Yuna but I had to kill Rikku in the process." Cid: "That's fine, as long as Yuna is ok. We can't have her sacrificing herself, now can we?"
The "rescue Yuna" as a plot device. Yes, we are her guardians, but come on... How many times do we need to play the save-Yuna card?
Flow of events considering time. Try to make sense of the flow of time after they kill Seymour for the 1st time, 'til they escape Bevelle.
The snow yeti breaks the ice; you fall more than a 100 feet to your death, yet you survive. Then Sin magically transports you to Bikanel island where Yuna is taken by the Al Bhed. Somehow the Yevon squad manages to get to Home, wreack havoc and kidnapp Yuna before your party arrives. Then they transport Yuna to Bevelle, prepare a wedding before you -who have the only airship in the world- manges to get there. It makes less than 0 sense.
After they crash the wedding they go to the -tediously annoying- cloister of trials to get Bahamut. Why? Isn't it painfully obvious you would get caught there? Even more stupid is the execution by sewer. We know Mika wants them dead (he orders his underlings to kill anyone who tries to escape); why not do it in a more efficient way? It's not like this method is a settled, or preferred form of punishment in Spira. At least as far as we, the audience, know. I may have accepted it if it was foreshadowed more. In the end, this is a double plot induced stupidity moment.
Why did not Auron tell the others about Yunalesca? I don't buy "you wouldn't have believed me if I told you" crap. Then why tell Tidus that Sin is Jecht? In the light of Yunalesca's case the Jecht thing would make sense at once, so why not? Preparing all the guardians for what's ahead, not just Tidus, would be a smart thing to do. The perfect opportunity to do this would be the campfire scene. It would make for a shocking reveal at the same time blend it together with the intro, making it more memorable. Instead we get a "This is my story" bullsh*t repeat. Is this were all those narrations from Tidus happened? And the story 'til now was all a flashback? Did he just narrate his whole trip to the rest of the party? ...Yeah I know it's not the case, but then, who is his narration meant for. We, the players? It doesn't sound like that either: "Listen to my story. This may be our last chance."
The plan to defeat Sin by song. Need I even need to elaborate on this?
The defeat of sin by blitzball and stuffed moogle toys. No one in the history have ever managed to defeat Sin by any means (except the final summoning of course), yet here we are fighting him with medieval (and stupid) conventional weapons. I guess it's expected in the spirit of jrpgs. That doesn't mean it makes more sense and is less unacceptable.
I could go on. In almost every scene there is something stupid, annoying sh*t going on that bugs the hell out of me. Still I recognise as a good game overall, but not because of the story. The themes and messages square tried to get across may be good though.