You're conflating "justification for" with "execution of" in this case. I thought I was being pretty clear, but I'll take the blame on this for not being clear enough. In a minute, when I respond to Ropen's post, I think you'll have a much clearer sense for what I meant about justifying these movies.
The tongue-in-cheek nature suggested by a winking emoji kinda gets overridden when it's followed by a statement like,
"but the battles don't just fall apart when you think long and hard about them, they often times hit you directly over the head with their stupidity." I trust that you can see where I'd misinterpret how tongue-in-cheek you were being.
Well, if we can postpone a TLJ debate for a brief bit, I'd like to continue nerding out one last time about this RO thing.
Although you may (will) disagree, I contend that RO tells us that the small exhaust port Luke fired into at the end of a long and fortified trench would've actually been there *by design* (as a means to destroy the whole station), rather than just by an arrogant Imperial oversight (as we believed for about 40 years).
How do I know that? Because the Alliance/Rebellion would've been using computerized analysis of those DS plans that R2 was carrying. These weren't pirates staring at physical blueprints while confusedly scratching their heads with their hook hands. The Alliance on Yavin had droids and computers with advanced AI beyond anything we have irl. The whole DS layout, and the means by which to reach the reactor, would have been isolated within minutes (if not seconds).
Using context from what we know about SW navigation calculations, and geographic tactical assessments, we know how much they rely on computerized data. So, aiming for the exhaust port tells me that is what the computer analysis determined was the best/only way to exploit Galen's designed vulnerability. You can speculate and assume any other scenario of Galen's if you choose to, but as you've told me before: only go by what you see and hear on screen. Doing so tells us that Galen either designed the most impractical "trap" ever, or the Alliance was riddled with ineptitude (computers, droids, pilots . . . the whole deal).
Yes! That sums it up better than I did. Thank you for understanding my point, even if I made it clumsily.
I think Luke's one-in-a-million shot has more luster, if not coherency, when it wasn't a designed flaw built intentionally to be exploited.
Two Death Stars wasn't a problem during the OT because we didn't know it would take longer than 2 or 3 years to complete one. ROTS ruined that by showing us that, nope, it takes a couple of decades.
And the vulnerability of Death Star reactors was fine when we could assume that you can't build a Death Star any other way (just maybe fortify it better next time - like with the Endor shield). But RO told us that the DS1 reactor posed a special vulnerability by way of intentional design flaw. That would now make any similar DSII flaw a plot/logic problem, since Galen Erso had to go out of his way to make the first reactor unstable. A second unstable reactor is now just ridiculous.
SW movies are like any other movie in this (or a similar) genre. When you scrutinize them too much, you find plenty of the same "problems" that YouTubers are having a field day with on the new ones. What's worse is that each of the five prequels muddles the plot logic of the OT movies more and more. The more they make, the worse it'll get - even when the prequel movie is enjoyable to watch. That's one of the reasons why it's hard for me to see how they are justified so readily by fans when compared to sequels.
I think I've stated my view of it enough (for now, heh heh) so we can just disagree on that one. 
