15D Don't waste time worrying about this as a "6,3". It's a "9". TLS seems particularly capricious in this area. (e.g. last week's DRTHORNE (7))
19D Charles Johnson's pseudonomous protagonist. S_L_A_A. I can see what it looks like, but I can't find any confirmation. Can someone point me in the right general direction?
SULTANA may be a better choice. Charles Johnson (18th c.) wrote a play called THE SULTANESS, in which the word "sultana" appears. And SULTANA has been used a pseudonym more recently.