https://pokemondb.net/pokebase/408485/what-the-most-efficient-way-shiny-hunt-every-single-pokemon
Are you including Sparkling Power Sandwiches and Outbreaks from Scarlet and Violet? Sparkling Power is quite literally broken, and some Pokemon can be isolated, and in S/V, outbreaks are easy to manipulate using Sparking Power Sandwiches and resetting the outbreaks. Of course, I see the flaws of this, since the game could possibly be patched so that you can't reset outbreaks easily, but even still, Sparkling Power is OP.
Additionally, how good is the Catch Combo Method? I don't have LGPE so I'm unfamiliar with how good the odds are.