*SPOILER*
My first play I took the V and Panam ending, and the overwhelming feeling is there are many elements and clues which suggest this isn't the end. Now, I may be clutching at straws but it just feels like it's not by chance and that it has been intentionally left open.
V returns with his body to Panam but is given 6 months maybe a little more by Alt, the AI who admits she cannot know the future.
We are given a parting gift by Johnny, "Never stop fightin", which seems a bit pointless for somebody who is going to die in 6 months-ish and whose story we cannot continue.
Amongst many holo voicemails from characters reminiscing with V in very ambiguous ways, we get a rather definitive message from Panam highlighting we are still with the Aldecaldos, we are still with Panam and she is intent on seeing us to 'make it up to us'.
And finally, V isn't dead. There is no solid information that this is posthumous. We hear a cough and 'fuck' at the end, as we heard over and over throughout the story.
Again, this may be my bias, being overoptimistic praying for some more Panam and V, but this feels like it is wide open for continuation. If it isn't intentional, its utter sheer luck that CDPR have foundations of a Chapter 2 style DLC.