Thanks for the offer!
As for my favourite Cosmere character, I'd have to say that there are some top contenders, but I've yet to finalize my choice.
Contender #1 is Wit, not Hoid mind you, but specifically his turn as the King's Wit because that remains the single best character introduction I have ever experienced.
Contender #2 is ShaiLu, because everything about The Emperor's Soul screams for a sequel of full novel-length. I need to see her other Stamps!
Contender #3 is Uncle Kiin, otherwise known as Dreok Crushthroat. Yet again a character who Sanderson has yet to plumb the depths of!
Honestly though, most of the characters Brandon writes are interesting in their own way, and could even have their own book, if he ever gave it time. It's what makes every character believable and fun to read!