I just finished my third playtrought of the game, this one going for the Don't Fear the Reaper ending.
First of all, I do see the canon ending being either The Sun or The Star since they are the only two that give a possibility to additionnal content. However, after seing the Don't Fear the Reaper (pretty much the Sun ending without some character dying), I think they will go for this one.
I previously stated on this forum how Mr Blue Eyes seems to be directly connected to a lot of plot holes in the game such as the Peralez questline. With the dialogue you get with him in this ending he clearly states that V wants Mr Blue Eyes to keep his end of their bargain. However, in the space ship, Mr Blue Eyes talks about the number of ressources V is gonna get from this heist, to which V responds something like I don't have anything to get from this. How I interpret this is pretty much that Mr Blue Eyes part of the bargain is the only thing V can get which is some type of cure or additionnal time to live. But, the data shard that seems to talk about V's future in this ending seems to be way less hopeful that the Iliad then you get with the Nomad ending. I already stated previously how I would see the Nomads coming back in a second DLC (if the Heist is the first one) where Panam will call V for help for whatever reason. Also, this ending makes it way easier for them to work around all the romance options.
Also, in my opinion, Panam doesn't really get the ''perfect'' ending her character deserves in any of the two endings and she's left with a huge plot hole either way. In the Star ending, she lost a number of close friends and has her hands full with her new duty as leader of the Aldecaldos which we could imagine impacts her relation with V. However, she has V at her side and the ending seems to suggest that V managed to survived or prolonged his life. On the other hand, the Sun endings makes it seem like she's happy in the badlands and we can imagine that not losing a single close friend is something positive. But, she doesn't have V at her side and you can see in her message that it hurts her, especially when she says: ''oh well, can't have everything - right, V? You know what I mean.'' Again, when she's offering to take V in a long ride, one can assume that he's alive and he could go and join her later down the road, which we could say is the best ending since V would be with Panam and she wouldn't have lost Bobby, Teddy and Saul, making her co-leader which would take a lot of weight off her shoulder since she would not have to lead alone.
Either way, let's keep this tread positive and let's see what the dev have for us, but I'm really hoping we'll get more side content with the great NPC they gave us!