Your answers about both Slate and Archangel are pure conjecture, which for me is the main issue with the story as a follow up to BioShock. BioShock was heavily invested in making this ridiculous concept same realistic, and gave solid, reasonable and understandable answers to the players questions; questions that the player never even needed to ask because Irrational understand the kinds of question the world they build would create. We absolutely understood the fundamental way that ADAM in the first game worked; it rewrote genetic code. That answer didn't need to go any further because it was a believable, satisfactory answer for the majority of players. It gave the necessary information without weighing down the story. Vigors are not given the same explanation here at all, and their attempt to fill in the blanks within the narrative as to why only a tiny fraction of the population use them, and only two of the six or so available, is laughable. Their explanation is really left to "Oh, they haven't been tested, could be risky"? That's total horseshit, considering what we see of them in-game. Consider some of these points:
Enough time has passed in the game's story for multiple "Vigor Solutions" to be found, researched and manufactured.
The Fair we pass through at the beginning of the game shows a handful of Vigors at stands, namely the Bucking Bronco and Possession. The others are simply being advertised. This says, with the same level of conjecture as you're giving most answers, that the Possession and Bucking Bronco are new while the rest are older Vigors, a fact supported by...
The fact that several areas and several pieces of equipment within the game run on vigor technology; the Shock-Jock. The vigor must have been around and usable for a decent amount of time if it's been integrated into how Columbia works, never mind the fact that it's been considered safe enough to be displayed with other machinery in public areas. This leads me to another point...
The kind of people who would have access to and use a Vigor like Shock-Jock would have been the repairmen and lower level folk of Columbia, the exact same people who take part in the VoxPop uprising later in the game. An uprising in which they need all the manpower and firepower they can get their hands on. But you're saying the same people who have access to these useful Vigors instead think "No, a little risky. I'll just run into battle with my rifle. Don't want my Vigor to backfire on me!" And what about the people being run out of Columbia? None of them thought to stand up and fight back using an easily attainable and powerful weapon that is constantly just lying around everywhere in Columbia with the "fuel" for the this weapon literally overflowing in every location?
Which brings to the largest point demonstrated by BioShock 1, having the ability to rewrite and remake yourself was a messy subject and, in part, the ultimate downfall of Rapture. You're telling me that in a city so obsessed with race and power, and with this all bubbling under the surface, that it wouldn't play a part and would be largely ignored by the entire population on both sides of the issue?
The Vigors feel like a massive blindspot in the story, and that's the problem with this game to me; it feels like they designed the game around the location and the "tear" concept, then Ken figured out the ending and they wrote backward from there. BioShock took painstaking measures to make the world feel believable, where Columbia falls short on so many aspects of vital basic elements of how the world works. And if anyone believes that those details were "pointless" in the first game and unneeded in this, then I wish I could be in your shoes because those details were what made the first game such an incredibly immersive experience, and when those key details about how this world works, especially when you include a Multiverse, aren't explained to a satisfactory level, then the immersion and the story fall apart for me. And don't say they've been left open to interpretation because some story elements like Vigors shouldn't be left open, it's just lazy writing.
