The Arasaka ending is literally called the devil end. The game is passing moral judgment on you for disappointing your BFF Johnny. No place for nuance here.
That's an interesting point, because if you've ever dabbled in occultism, you know that the Devil in the Tarot isn't necessarily an evil thing. It could be, but it depends on the surrounding cards. Trouble is, Misty's reading isn't orthodox Tarot. Plus also she's a Streetkid, what does she know about the options re. aligning with the most powerful corporation in the world?
I quite like the ambiguity of it. After all, the great Transhumanist dream is a) immortality via uploading, and b) onward to the stars. Of all the factions in the game, which is most likely to achieve that? Arasaka obviously. The flaw in that ointment is that Saburo is a control freak and wants to keep it all under his and his family's control forever (the sinister line from him on the newsfeed at the end, "Change isn't necessary if you have perfection" or something along those lines). On the other hand, your bro Takemura, who came from humble beginnings like you (at least if you're a Streetkid as my main is, or a Nomad), has been right in the thick of the Arasaka empire for years, about as close to the center of power as you can get. So if he ultimately trusts Saburo's intentions (e.g., he hasn't smelt anything fishy about the whole engram/Mikoshi thing, like the engrams will be turned into slaves of some sort, or whatever) maybe you're best off taking the Deal? Certainly if you've ever felt the lure of Transhumanism you should, as it's your best chance at that future, as you, retaining the continuity of you from your birth. (Being absorbed into an AI might seem somewhat in the same wheelhouse, but it's not at all, although in a sense it could be a path to even greater power ultimately, but then it's definitely no longer
you who will have that power.)
The play of humanity vs. transcendence mixed with the question of identity - it's all good stuff really, and it's very much in the vein of the great cyberpunk classics and that whole period of techno-optimism and Transhumanism from the 80s to the 90s.