Flex que, this is Balanced?

I played 63 games in flex q already, with an amazing win rate.... I even spanked "Imaqtpie" yesterday in flex q on his stream with 24 thousand something viewers.... The fact that I go from plat 1 to silver in flex..... like I think I lost maybe 5-10 games and only because I went against rf legened and like 3 other players... I was master in solo q when I quit. My mmr still reflects that. The fact that the grinding I did the past few days was for absolutely nothing.... I know its preseason, but rito even said that preseason mmr effects your starting mmr during the start of the next season... Like WTF let me grind my fingers to the bone and take my work away from me without even adjusting my mmr for the 64 games I played in flex already... Makes me wanna quit the game again. Riot just makes mistake after mistake..... Also my thought on flex q before they just changed it and ruind it further, Once you got to higher apex tiers teams were ALWAYS balanced.