To me, all the options are mediocre at best.
If Game Freak remakes Black and White, and by Game Freak I mean the actual Game Freak, it'll be based on Black and White with no Black and White II content. Those days were they took the original versions and greatly improve over them, like they did were FR/LG and HG/SS are a thing of the past, so there's literallly 0 chance of them doing the extra effort of mixing content from BW2 into BW remakes.
With that being the case, I actually prefer the ILCA treatment. Yes, they won't be as great as past remakes done by Game Freak, but it'll probably exceed in quality what Game Freak is able to do now. In fact, it won't surprise me if somehow, and for some reason, Game Freak decided to just get rid of the Battle Subway as a whole, making remakes with less content than the original games released for the Nintendo DS in a 256/512 MB cartridge.
The good ending would be past-Game Freak doing another HG/SS with BW, but since this isn't happening, the not so bad ending is ILCA being at least faithful to the originals while improving the teams and so on like they did with BDSP. No matter what they do, games will have less available mons than the originals BW, so they actually have less content no matter who ends up making them.