The rewards are for your skill level and not your behavior.
I think that if someone is unfit for rewards, they should be excluded from ranked play or playing the game at all. There should be more perma bans to be honest.
Treat it like baseball, 3 strikes and you are out.
Strike 1 = 25 game chat restriction and loss of First win of the day bonus ip for 25 games.
Strike 2 = 7 Day ban and 25 normal wins (+ lose ability to earn ip for 50 games), before being able to que ranked again.
Strike 3 = 14 Day ban and 50 normal wins, ( + Lose the ability to earn ip for the remainder of the season) with the warning that your next offense in the current season will result in a perma ban.
Everyone that does not get perma banned gets a fresh start in the next season. Severe and clearly defined punishments for offenses would do much to curb misbehavior. Someone who was punished earlier this season and reformed (hopefully) still losing there rewards (that are based on skill) is silly.