The lack of a functioning Blacklist for PvP is my #1 issue with CC, and the reason I've stopped playing for the time being.
I don't care about trivial things like chat spam. My problem is that because you can't derank out of Crystal, it's full of bored idiots throwing matches on purpose,
because they have nothing better to do and there's no penalty since they're already sitting at 0 Crystal Credit.
If it's a one-off, whatever, but I run into the same people match after match, day after day, and my only recourse after eating a guaranteed loss,
is waiting several minutes before queuing again and praying. During offpeak hours, the only real solution is to stop playing entirely.
It's frankly insane that SE hasn't given users even the most basic tools for dealing with such an obvious problem.