Would like to understand what is going on with Dominion matchmaking

You win a few matches, get up in MMR, nice games, cool people. When you think the game will get better because in theory higher MMR = more skilled players that understand how Dom works. You get more trolls, more people with 10 ~ 200 wins that say they know how to play but defend a tower by staying under it, and they still want to teach you what to do. You get more people that won't follow the tank into the jungle no matter how much you spam the assist me ping after seeing an enemy alone in the map. And this continue till you drop your MMR quite a lot. Then you rise again, and everything repeats. It's getting frustrating. When you have a match with cool people it's fun even when you lose. But holy shit Riot... things are getting out of control. I know it's not a mode that people treat serious (thanks to Riot itself) but damn... please add ranked to it so at least I can find more players interested in the mode and maybe form a team. For God's sake.