A lot of ppl including myself experienced getting -15 on loss and no more then +9 or so with a win constantly. Also que was instant, i did not let it drop a single time.. i think this is due to MCH with a very low population that causes lack of casters and then you lose much more then you should with a loss and gain less then you should with a win. For example with a 4-2 score without que droping i am in a negative rating from that. I know this wont be fixed but i wanted to say it anyway
That's why i'm stuck at 1700 for 2 weeks, and im 2k exped multiple times and already geared (im trying to get 2050 mounts and why not, try 2k2). Everytime its a thundercleave, or a warrior that makes me play like an holy paladin (im priest) and 90% of times its a loss, they do too much pressure and my team is scratching their balls. At the end its always -15, then I need to recover with 2-3 arenas with 5-8 points. I started this morning aiming for 1800 after 3 hours i ended up at 1600..just saying (And i got a nice w/l)
Your team with hihger mmr than enemy team losing 15 points or
your team with lower mmr than enemy team winning 5 points
is working as intended and not broken