ARAM Champ Select Idea: Being able to see a person's mastery on a champion before trading

So I play ARAM I lot, I have every champion, and I really love the mode. My idea is that when you are in champ select, and you have the option to trade another person, before clicking the trade button, you should be able to see what mastery level they have on the champion.

I think this is useful because:

1. When someone is trading me, I want to know if they are doing it because they main the champ or they just want to play it. For example, if I have and they have , and they want to trade, I have no problem doing the trade, but I'd rather play Brand. Seeing they have points on Brand would make me more inclined to trade. Even if they have a champion I hate to play, I'll still do the trade if I see they main the champion I have.
2. When people want to trade, I decline to trade, and the champion I have is their main, they don't say anything the majority of the time, and if they do say something, it is in game...kind of late, but it has happened.
3. If I am indifferent about the champion I have, I'd like to see who has a mastery on it, and offer a trade. I normally just play the champion I get, but if I see someone has masteries on it, I'd at least ask if they wanted the champion or not.

That's all I really have to say about that, just thought it would be a useful concept to have. I know there are potential drawbacks to it, like people being jerks and denying you a champion because they can see your mastery, but I think the results will be more positive than negative.

P.S: While I'm making an ARAM post, bring back support items and stop their gold per second I miss my talisman , secondly, for the the love of Urf, stop dodging. Don't play the mode if you are going to dodge, it is actually more annoying than being against all at once