These missions are making Diamond MMR normals worse than they normally are

I'd really appreciate it if you could fix this retarded algorithm, and not make it stick me on a team of four solo players against a full 5-man premade after 4 minutes.

This is happening in almost every single game, with one team being a 5-man pre-made trying their hardest for missions, and the other team having five solo players learning new champions. It's a massive waste of time.