In my opinion, Cruise is probably more powerful than Vision, especially in a format without Shardless Agent. Assuming I'm right, this makes Vison's banning even more suspect—or at least points to the extreme likelihood that Treasure Cruise will see the banhammer sooner rather than later.
The last Modern-legal card that has been making a huge splash in Legacy control decks is Ancestral Vision. While not every Jace, the Mind Sculptor deck in Legacy plays Ancestral Vision, a great many of them do. The combination of Ancestral Vision, Spell Snare, and other counterspells lets control decks draw cards very cheaply without getting behind early on, and that's powerful enough that we feel safer having it banned.
The card was originally banned out of conscientiousness, but we don't even know for sure that it's too powerful for the format. Frankly, we don't even know if it's good. With quick combo kills out of nowhere and Goremand being played in nearly every blue deck, it might simply be too slow and unreliable.
I don't think this discrepancy can or will last much longer. But the question is this: if Magic was a democracy (which it is most decidedly not, but let's pretend for a minute), what would you vote for?
I'm not giving an option for the potential third answer, which would be to leave Vision on the banned list but continue to let Cruise run rampant in the format. If you believe this should be the case, please comment below—I'd love to hear your reasoning.
As for unbanning Ancestral Vision and banning Treasure Cruise, that seems like an unlikely line for the DCI to take. It's certainly possible, and there's good arguments to be made for it, but I would be surprised if the message sent was, "Hey, this draw-three is too good for the format, and we always thought this other one was, too, but what the hell, have at it, boys and girls." If we do end up in a Vision-legal/Cruise-banned world, I think it will take some incremental steps to get there. What do you think?