Actual the MM + ranking system is bad.

About 20% of the games are fair, the other 80% is a team bether, which means that the other team is farmed. Is that your idea of your MM?
Also when you got farmed, you mostly get -ranking, even when you are first in your team. Is that your idea of your ranking?
And I also see no reason, why your MM doenst realy looks for the setup. For example: I had a lot of matches, where our team had no ice witch / sapper and the other team had 2 of it. Why do you dont look at the setup? Also it is a big disadvantage if the own team has no ice witch and the other has one, because ice witch is very powerful for teamplay.

And other point is, that there are many players who now gives a pony to game objectives (for example to carry the ball), because it gives 0 Points. So your ranking system also destroys teamplay.

And the best confirmation why your ranking system sucks is, that many noob healer has now 6k+.

Please change the system. For example you could give ranking points for team goals (carrying the ball, XP for hold a point) and so on and of course think about your MM...

What do you think about the MM / ranking?

I agree. Support should be the same in both teams. Now this (no support vs full support - how many times have i played games e.g. 'ice+tank+healer vs tank'...) always makes the game imbalanced. Also I don't think it is good when it is 4vs3 orcs of similiar bv and the 4 have a healer with bv 5k and the 3 orcs have a healer with bv 3k. Not once there was also a situation where one team had orcs at about +1k bv than their enemy orcs. And replacing it with a better sapper or gunner on the other team isn't imho a good solution.
Public games here are USUALLY imbalanced. This is bad.