So, one of the common ideas I've seen thrown around when it comes to fixing the X-Wing is to put "Rebel Only" on the fix card, preventing the T-70 from taking it. The logic here is that the T-70 is Resistance, not Rebel.
This brings up an interesting conundrum with the new Falcon, however. If this idea really works the way people suggest, then wouldn't it be impossible for the Resistance Falcon to take Rebel Only crew?
Now, obviously, this is not the case. The new Falcon can take Rebel only crew, just as the TIE/fo can take Imperial Only upgrades like ruthlessness. Which means the idea of using "Rebel Only" on an X-Wing fix simply wouldn't work, making it much more difficult to fix the X-Wing without making thr T-70 stronger.