Oddly, I feel like the ending's biggest change is that it establishes V probably does live in "Never Fade Away" because the ending establishes the cure the NUSA has came from the same person V is working for in the Heist ending.
PROBABLY.
But not CERTAINLY.
Perhaps... although V being now an engram may complicate things, is V now still running on V's brain or is V now running in the relic as a software emulation? Can someone plug the relic from V's brain into an other person and have with V happen what before happened with johnny?
As I have explained in my earlier post I find most endings to be very forced (lazy writing) once V becomes an engram there is no reason they wouldn't be able to eider stay in the body indefinitely (if Jonny can why not v that's not plausible), or the body would have to die mo mater who stays in it, in which case being an engram would allow V to just switch to an other body.
The entire it needs to be a match thing is not very believable in the end Jonny and V surely were no matches eider and it worked. Saburo choosing his son's body surely had legal reasons above anything else, in the end the legal standing of an engram was not established in the legal framework what would be better then to take the body of the one person who would legally inherit everything one owned anyways, solves so many legal issues, howeever it would be a pity if someone would to leak a recording of yourinobu killing saburu, and now saburu in yourinobus body being convicted for murder to life in prison for killing well himself? LOL
It is possible that the "Never Fade Away" and the Aldecaldos ending are boot setting up for the announced sequel in which we can only hope V will have to finally find the long sought for cure.