Apparently Mayweather phoned Khan last week, but if you believe Khan, Mayweather only got through to his pal and begged him to put Khan on the phone. Khan relented and Mayweather apparently told him he was a great fighter and referred to him as champ throughout the conversation. It sounds totally un-Mayweather-like, and the story has the feel of the BS fiction Khan fed the press a couple months ago about how he sparred and took Andre Ward's best punches.
I don't think race really comes into with people's perception of Amir Khan... I just think Khan lacks the charisma or wit to pull off being arrogant, and that is why so many interpret him being a twat.
Amir Khan's issues in respect of his chin have been attributed to his weight. There is a reasonable chance that, once he has acclimatised to the 160 Ib division, Khan will be able to absorb GGG's punches. The more salient question is, will Golovkin be able to take Khan's rapid and heavy counters?
Will ignore that aspersion.
Like it or not, Khan has the weapons to be a four or five weight champion, but he has not harnessed his gifts to the max as of yet. Hunter has the credentials to make Khan realise his potential.