Anttyaz Not gonna argue every single type and things while I'm on my phone, and if we keep doing this it'd just be a pain lol.
One thing which I feel you are wrong about is the statement that "no mon is broken by itself". There are a multitude of mons that are broken by themselves, such as M-Mence, M-Kanga, and almost all the cover legends. In monotype itself, Talonflame was banned not for its support, but for the fact that it just ran through multiple types itself. You could say that the support necessary was a hazard remover, but look at Fire. Torkoal isn't necessarily the best hazard remover in the game, yet Tflame was still banned.
Also, none of the mons I suggested as checks did I 'have to go out of my way for'; I honestly thought of them in less than 30 seconds each. All of the mons and sets I posted are either already on said mono (Elec, Fire) or would require minimal change to the team itself that would hardly hamper the team's overall efficiency (Fighting, Flying) The fact is that Sableye has to rely on his teammates to beat mons that are commonly found, and who likely also have teammates that can wall/break typical Dark mons. While you had a solid point in the Aegislash ban, a key difference is that in 3 mons alone, you could wall almost the entire metagame, and most monos required extremely obscure checks to beat that 3 mon core. Sableye and his teammates are nowhere close to this; Dark would have already been a top tier threat along with Flying and Water if it was.
Point is, Sableye has to rely on teammates to deal with very common mons on nearly every type, and if the opposing team is any good, they will have mons that also deal with Sableye's teammates. Then, it becomes a game of skill: who can break the other' score first? And if that's how games are won, then the meta is healthy, in my opinion, as skill has now become the key factor in winning.