I feel like the balance team is the biggest problem for imbalanced matchmaking

Hear me out.

Let's say a champion is weak for a long time. The people who love the champion and play it anyways end up falling in MMR for a while until they get somewhere that they can win 50% with the weak champion. Meanwhile most players don't see the champion at all in most games. Several months later the champion is buffed to be strong, and that player now may have a much higher likelihood of winning because they're still used to the champion AND it's strong now AND their opponents aren't used to playing against it. So they get really fed, and it looks like matchmaking is really bad, even though it was almost solely caused by the balance team leaving the champion weak for so long, then buffing it all at once.

On the flip side, you get people that abuse OP champs all the time. They rise in rating due to winning matches on OPs, but don't really have the skill level to belong at their MMR. Then you get a few patches where nothing is crazy op (or few enough that they're all banned) and these players feed and lose a lot of games. People think it's bad matchmaking, but again it's the balance team letting these OPs exist for long enough for people to gain meaningful rank off of them.

Ultimately, the idea is that each player isn't ranked only on their abilities, but also the influence of the champions they're playing. Since some people stick to champions (and therefore benefit when nothing is OP, or when their champions are strong, but suffer when their champions are weak) while others play a large pool or jump on what's fotm (and therefore benefit when something is really OP but suffer when nothing is), it adds an extra layer of complexity to matchmaking that isn't accounted for.

When champ X gets buffed, you don't boost the MMR of all X- one tricks. Those players will likely do a lot better than normal for a chunk of games until they climb thanks to the buff though. The opposite on nerfs.

I'm not suggesting that you change MMR based on what champions someone plays of course! However this may imply that balance should be a LOT MORE FLUID, contrary to the balance team wanting to go for bigger changes and then adjust to a middle ground. From a matchmaking perspective, a longer time of smoother changes could be hugely beneficial, and this seems to be overlooked.

Thoughts?