As Vyzzuvazzadth says, the "Setup and exposition for conflicts, confrontation and resolution within an installment needs to happen at the beginning of a game", the bombing mission doesn't tell us "Shin-Ra Inc. is lead by a oppressive tyrant and needs to go down." It's "these Mako Reactors are killing the planet, and we will all die unless they are shut down." You leave Midgar with six reactors operating in full swing. Sephiroth is the bigger threat. But you don't know that yet, if the game ends before Kalm. New players end the game not knowing why they stopped trying to save the world that is in immediate peril. It's problematic in it's own right.
It's clear that Shinra is the culprit. Barret keeps referencing them. So it's very clear from the start that Shinra is bad and has to pay for sucking Mako out of the planet. And what you're criticizing can be easily solved by a little more explanation. And as I illustrated before, Avalanche's motivation for what they are doing keeps shifting because circumstances change and call for different actions. If Avalanche kept ignoring everything around them and kept bombing reactors until all were gone, would you be happy? That would make for a very bad story. There would be no growth, no change, no evolution and Avalanche would probably meet their end halfway through. They need to adapt to what's happening around them and to them. Also, while bombing all reactors would stop Shinra from sucking Mako out of the planet for a while, everyone else in Midgar, especially the citizens would suffer. And I believe that even Barret would see that eventually, if they kept playing that bombing game. Heck, the first reactor bombing already caused several civilian deaths.
My point is that leaving Midgar is not the objectively perfect end point for Part 1 it's currently presented as. It neither the first nor the last tme AVALANCHE adjusts it's active mission and it's not the end of them fighting Shinra. It has it's pros and cons as an end point. Maybe it's favourable to Junon but moving Jenova by no means addresses it's substantial cons.
Moving Jenova was by no means meant to address any cons to ending part 1 at Midgar. The point was to present another possibility, a "what if" if you will, in the case that referenced leak was legit.
I see what you're saying. However, taking all pros and cons into consideration while putting the most weight on the story (which is important for a story driven game that is supposed to feel self-contained and its own experience), Midgar wins out. the gameplay structure fits for a full game experience and the transition from the whole Midgar arc to the Sephiroth/Jenova/Reunion arc is (in my eyes) without any doubt the best choice for a cut in the whole FFVII story, only second to the summoning of Meteor.
To make a game's story feel complete and not chopped off, you need an appropriate resolution to what came before. There is no such point between the flashback and the summoning of Meteor. Not without heavy rewrites of the story and chain of events. Midgar wouldn't need nearly as much rewriting to feel like a single cohesive game.
The only point I might be able to get along with is Nibelheim, if they expand the crap out of that place and add some epic confrontation in the resident reactor (that first visit had way too little significance in the original game, given its relevance to the plot and Cloud's character arc).
However, then we'd probably be looking at 4 parts and I'm not sure if that's feasible.
(Context: I've had an interesting discussion on Discord last night about Nibelheim as a possible splitting point.)
