The introduction of Varrick is one of the reasons I liked Season 2 more than Season 1 of Legend of Korra the first time I watched it.
Varrick is a character that Korra needed, and not just for his humor. In a world like the Avatar series takes place in, it's easy to paint everyone as either black or white, good or bad, on the heroes side or against them.
Varrick is grey for most of the series. His interests are his own and he'll gladly help if it furthers his plans and refuse if it hinders them. Have a morally grey character who can become entangled with the other characters plans is always fun.
Plus, he's hilarious.
But I bet Varrick has a dozen variations on that coat anyway.