The beginning is... poor. No arguments here. I'm not sure how much of the nitpicks are genuine or just joking, but I think most of the stuff you go on about the city is overkill. The game might have been upgraded to HD but it's still working off PS2 mechanics, and they didn't have the technology back then to really let the vastness of Zanarkand sink in the way they could today. The recycled character models is a fair complaint but I can also see why they'd do it. Save on time and resources. I'm not going to defend the voice acting, though. Voice acting is not Square's strong suit and I think the direction, dubbing and voice actors themselves all contribute, at least in X's case.
I don't think Auron was trying to call Sin either. I think he was just like, "I'm cool and a badass so I'm going to ride Sin because I can." I never took anything more from that scene than that. The whole thing with the sword is legit and such an easy fix if they just had him able to hold it with both hands in the beginning because he's already athletic like you said. It's not going to make much difference later anyway since he's able to wield it like a pro by the time he gets to Spira. I love your analysis of Blitzball and I sadly can't remember much of the fall off the ledge so no comment. Final Fantasy utilizes anime logic a lot around this time if it wasn't obvious already since VII. I'm enjoying this playthrough immensely so far.
Look at me, managing to make a post longer than a line.