Personally, needing 100+ games to normalize and the very high variance in games is not satisfactory to me.
Let me give you a concise situation: smurfs.
If we had a system which could quickly determine a player's actual skill based upon their performance then they would rapidly move out of lower elos, and more quickly end the pubstomping. What's more, it would reduce or eliminate the problem of 'premades' with highly differential skill since skill would more rapidly be determined.
On variance: It's taken me over 200 games to end up at a place where winning and losing is largely normalized to my play (it still isn't, but it's clearly approximately where I belong). That said, I still see a very broad spectrum of team performance. Now, this could be due simply to the natural human variance. I am positing, however, that it is more likely due to the nature of matchmaking itself. If we had a far better assessment tools for skill identification, then the games would be more evenly matched, and more enjoyable for us all.
I do not see this as marginal in the slightest. They've spent millions on ping, and from a statistical perspective, the value of an experiential game of quality is at least on par with ping. If you could make the same level of overall systematic improvement to consistent game quality as they have done to ping it would positively influence the community on a massive scale.