Please combine normal MMR and ranked MMR.
as it stands, we have a system that will match plat/diamond players with bronze/unranked players.
Because of the difference in matchmaking between normals and ranked, testing something in normals before ranked often has no real meaning (Great, you can play Vayne against bronzies. Wanna try your luck against people who are actually in your tier?), low level players just get fucked whenever it happens to them (wtf I am only level 25 why are my opponents plat?), and high level players get really irritated when they have to deal with this matchmaking during preseason (not much point in ranking up in preseason if it doesn't count, so some just play normals while we wait for ranked to startup again).