i think most of your post is spot on. I do take issue however with your assessment of some of the pilots and the empirical data. I won't go into specifics of who can do this or that because this forum is absolutely packed with people singing the praises of their great new list which uses a U-Wing and has gone 4-0 in games at their local FLGS. It's all white noise now.
I do want to touch on empirical data and competitive lists and play. First if winning a Regional or System Open is your mark then you are correct. It if making top 16 (which I would consider a better indicator of list/ship viability) then the data changes. There is also an important point to make regarding upper level competitive play. It discourages risk. The people who are in serious contention in one of those major tournaments is almost always going to select a list that is a proven winner and tested against the current meta, or a part of the current meta. The nature of top level competition discourages big risk in list-making. And honestly there are few Rebel lists right now that aren't big risk.