All of the 40k books have their own setting, which is another thing to keep in mind. I think that was one of the best things in those books.
The flipside of that was that each corebook also introduced the players to the 40k universe as well, and similar NPCs in the back, and the same "this is an RPG" intro, and a ton of the same skills, and talents, plus an adventure (which isn't exactly up everybody's alley).
…so even if the core rules have a few differences (auto-fire changed a bit over the books), there was a lot of similarities. And then someone (who actually reads from front to back and compares like some sort of lawyer) would finally notice that some of the talents that the players remember from the first book are different in the second of third book, and nothing in the book points that out (each game line was written as an independent stand-alone game), and just hunting for these alterations can be emotionally taxing for those who enjoy these games.
Those are alterations that I think the Beta was meant to address, and I hope it works out that way. We will have to wait and see if Dodge works the same in EotE as it does in AoR and F&D (or whatever their names were, can't recall right now).
I think there will be Technician equivalents, and Gun for Hire, and at least something similar to Smuggler and perhaps the others. I kind of expect to see the order of some talents rearranged at least a bit. Like perhaps the Age of Rebellion version of Outlaw Tech will get Jury Rigged sooner, or more of them.
But I suspect there will be an addition to the rules set for each new game line: some military aspect for AoR, adherence to the Jedi principles for the Force & Destiny game, or whatever for the next line (assumption. It could end with only 3 lines, but…). These extra rules COULD be ported to other games, but from what I've seen with the 40k games, they seem thematically appropriate to each game line/setting, so I personally wouldn't want to mix too many ingredients into the Alderaan stew, so to speak.
With that line of thought, Dark Heresy didn't have any "extra" rules, it was the baseline, like EotE. Rogue Trader gave access to legions of shipmen, an endless line of credit/cash, and a ship as impressive as they come. I figure AoR will change the tone and perspective of the game enough that something like controlling a Rebel base would be the standard (in place of a ship and Obligation?) and I think F&D will make the Jedi Principles and the line between the Light and Dark a focus of the game.
So, TL;DR -- I love the settings they write, and hope that they will make the core rules separate. My wallet would appreciate that a lot.