That can’t be the case because he threatens Kylo with the possibility of possessing him and of course is clearly intent on possessing Rey at the end of the movie.

In all likelihood Snoke wasn’t deformed at one point but he degraded due to Palpy’s possession. So he killed all of the kids that would stand to threaten him before realizing Snoke was also imperfect, but necessary until he could get Kylo to him.

EDIT: I think I’ve spotted the difference here. Snoke and Palpy’s current clone were created at the size they are and possibly both without a soul for easier possession. Whereas these children clones have to grow and have their own free will in the process. It works and makes sense.