1. Include a key next time so we know what we are looking at.
2. What is your MMR we have no frame of reference.
3. The very low MMR's could be because that character hasn't been played in a while, the mmr system does odd things when your mmr is old in order to check if its still accurate.

Other than that it looks like you are facing people from 900-1800 on average.

I don't know how you got the 2400 guy because they brought in a 1900 threshold yesterday so you shouldn't of been able to get any1 over 1900 unless you are also over 1900.

I imagine your mmr is around 1200-1400 based on this, so that means its going + or - 400mmr, so the system seems to be working fine bar the 1 anomaly.