MMR needs a rework. I just played as a lvl72 (MMR 32%) Antagonist against a team of completely new players (the highest being lvl 9, the second highest being lvl 2, and the other two being lvl 1). Needless to say the match was over in 5 min. How can anyone expect these types of player to "Get Good," if they get curb stomped by high level Antags with what I assume is a lvl 9 mentor?
On another note, I do think the idea of a mentor system is great, but carrying an entire team of new players is not fun gameplay. The other day, I lost ~10% MMR (was originally MMR 42%) because I was constantly teamed up with 3 other players who had little understanding of the mechanics of the game. In EVERY match (literally), I'd have at least 2 members disconnect from what I assume is pure frustration because they were constantly dying every 30 seconds. I think the best way to correct this would be to have at least 2 high level players in a mentor match, because without any decent way to communicate to these new players, they will just keep dying due to poor understanding of the gameplay mechanics/objectives/tactics, and the gameplay will just be unnaturally difficult.
Additional notes; for every new player in a match, an additional 20% exp should be given to the mentor, otherwise it's not rewarding to play a 30 to 40 min match with a team of new players to only get 20% extra exp.
Extra notes; I think new players should be considered NEW players for mentor matches until they reach level 15. No offense to any of these players, but a lot of them don't seem to understand any of the game mechanics until around lvl 20. I've seen many players at level 15 die from very basic things, such as charging straight into a mob without any backup, or staying outside of sight from the beholder (not dying once but repeatedly dying from the same thing every 30 seconds). These players haven't gotten accustomed to the playstyle necessary to become a mentor themselves.