Ok, but the point still stands. You say the A Ranks deserve to be there, and you aren't talking about the low ones. So that leaves the giant kerfluffle of people in the B ranks who can't hit A rank, correct? Well, there definitely needs to be a group in the middle, as not everyone can be in the A ranks. If you were really good, and deserving of the A rank, then you would have gotten there or are close to it. Yes, there is some rough luck in teams at times, and I do think the Win/Loss point spread could use a slight tweak, but what about all the times that those players WERE on the good teams? Should they be penalized becasue they happened to have good luck, since if we are going to give a bonus to those who lost? It would only be fair to give a hit to those who won to keep it fair. Things have a way of balancing out. That's the nature of the beast when it comes to ranked ratings.
Now you see why I prefer to play TW instead of Ranked. It's a lot more fun when you aren't dealing with things like this. All the rankings do is make people cry and moan on why they aren't higher up, and that everything is broken because they have bad luck every game. Not saying every low ranked person is bad, as I myself am still in the C rank due to only playing a few ranked games because I know how people get in them (yet I win a good 75% of my matches in TW, and have won all but my first in Ranked matches), but those in the higher A ranks tended to get past any luck in the lower levels, or, you know, simply overcame it.
Honestly, I think this system is very good, even with the randomness, as while yea, there is some bad luck involved, those who make it high up got past the system, and it's not made to give everyone a gold star A+ 99 rank. It's also extremely fair, as everyone is in the same boat, and everyone has dealt with the same good and bad with teams. Adding premade teams into this system will actually offset any balance right from the get go, as you have stated yourself, teams that have worked together a lot tend to do better. So, that gives those teams way more of an advantage than someone who queues solo, and that's not very fair now is it?
If they do add a ranked party system, I hope it's a separate rank. Otherwise, it would cause a rather high offset in the balance of the system.