This is actually some random thought which popped out in my head when I'm waiting a ranked game to be started. We all know every champ has a line when picked, normally that line indicates the champ's personality, MO or stuff. I'm always really into quotes (the first time i came to this wiki i'm just looking for collections of champ quotes, for real), I think quotes are a very good way to complement background stories, make champs and interchamp relations feel more real.
So this is what i was thinking: maybe when a summoner ban a champ, he/she will have a specific line about how he/she feels or wish to express. Good-hearted champs may express their goodwill and wish the summoner victory, malevolent ones sneering at summoners' decision to leave them unpicked, some champ might just be upset for being overlooked or being feared, etc. I've had lines for several champs just now, and Im still brainstorming about the others. Examples like:
AMUMU: (when banned) Alright...I know I shouldn't be here...
AZIR: Shurima will be watching.
BRAUM: Braum will be with you next time!
CHO'GATH: I sense fear...
DRAVEN: And now this match is barely worth watching without DRAAAAAAVEN
GAREN: Fine, but fight with honor!
JINX: Ban the cops! Ban the cops too!
LULU: Where did we left off our game, Pix?
SION: YOU DARE BAN ME?
TAHM KENCH: You just missed everything that you want so badly.
TEEMO: Well, I can use a day off duty.
TWISTED FATE: Looks like you feel very lucky for yourself today then.
VEL'KOZ: I think these subjects are trying to hide from me.
ZILEAN: I know the ending of this match, find out by yourself then.
These are but a few, but I think maybe some people will like the idea anyway. Worth discussing for me, let me know about how you think~