I've been fine playing killer (and survivor) since the SBMM/MMR was introduced.

With the preface that I know that Rank/Grade means "nothing" (or it's supposed to not mean anything, though that's still up for debate since some of the inner workings of the system have been revealed), I was Rank 1 at both killer and survivor before and since the implementation. Before, I would run into a lot of tough squads with any killer I played -- learning new killers or practicing with ones I needed work with at Red Rank was a near impossibility. I did get occasional games where my lobbies were inexperienced, memesters, or lower ranked, but they weren't all that common. A lot of games at that level were sweaty on both sides (not necessarily bad -- people are naturally competitive, so that's to be expected by anyone who is playing to actually try to "win").

Since SBMM went into effect, the killers I'm very experienced with or have strong track records of success with -- I'm getting strong lobbies, but that's what I would expect, and frankly, they haven't been much different than what I saw prior to the change. Even so, I'll still see the occasional lobby that plays like they're not at that level -- I think that getting people into lobbies at a reasonable pace is still taking some precedence over the matchmaking itself during peak times (which is why, regardless of killer, I still get instantaneous lobbies during the evening/night hours due to the lack of killers/large numbers of survivors playing during those times).

The killers I've needed to practice with, hardly play, or are just learning, though? I've seen a definite difference in the opponents I face (as in, a drop in their experience or skill level). While I've occasionally had some head-scratchers here and there (again, I think due to the system prioritizing getting people into a match at some point over everything else), most of those games have seen me facing people who are good enough to be a somewhat competent challenge (due to my being experienced at basic killer mechanics overall) but not good enough to keep me from matches that I can learn, practice, and actually accomplish what I want to do in a match with someone new.

Since SBMM, I've gotten better at killers I never thought I'd be able to accomplish that with (Huntress being a prime example), I've snagged multiple Adepts (including killers I've just picked up playing, like the Twins, who the few times I played before SBMM I got curbstomped over and over -- now I've actually been able to practice with them and -- gasp -- had fun playing them), and overall my experience has been not perfect -- the system can definitely use some tweaks and changes to improve it -- but it's been more fun than I had before in the old system (when, to compete at Rank 1, I only played certain killers and specific builds if I felt I wanted to have a chance).

I know others have said their experiences differ. I'm not discounting or dismissing their opinions or experiences, just stating my own, so that's simply what it is -- one person's experience (and I play close to 40 hours+ a week, so I have a lot of time in the game). I do think that the people who say that EVERY single match is a sweatfest of SWF Death Squads or sweaty Nurse/Blight/Spirit every round that ends in a 4K are exaggerating the reality of the situation -- or they're living on a Bizarro World that I'm thankfully not getting a chance to be a part of, I guess. Again, take all that for what it is -- my experiences with it.

K’s need a buff in general. Bring the fun back. Even as a survivor I appreciate and have fun with a powerful K