For what it's worth, I'm in agreement with Ruko. A blanket ban on things that induce Type Changing should be included. It's hardly Mono-Type if one or more Pokemon in the team can change their types at will. And it's not fair to, say, tell the Flying and Dragon Monos that they can't use 'Zard X, but the Water and Dark Monos are a-okay to use Protean Greninja, which will almost never be a Water Type or a Dark Type, because Protean Greninja is made to counter common weaknesses to both of said types.
This ban would only completely deny Ditto and Kecleon. Castform's Forecast means that it would likely also have to go in case anyone runs weather. Protean would be out, but Greninja could technically run Torrent. This would also ban Camouflage, Reflect Type, and Conversion. Three Pokemon, Three Abilities, Three Moves. Hardly a debilitating blow against Battlers, who will still have well over 600 Pokemon to choose from.
As far as Stealth Rock is concerned, I am also in agreement with Ruko. I noticed you mentioning Talonflame in chat, but Rock moves are plentiful amongst Non-Rock Types, to my knowledge, so Stealth Rock is hardly the only counter to it. Plus, as Ruko mentioned, it completely ruins a number of other teams, and there is absolutely nothing stopping Stealth Rocks from being put down again once the Defog or Rapid Spin user are KO'd, again, to my knowledge. Once again, it is not fair to the rest of the teams that Stealth Rock should stay because Talonflame and 'Zard Y are scary Fire/Flying Types.