Based on the most recent plot leaks. Bleeding Cool got their hands on a copy of the character biographies being used in open casting calls so let the rampant speculation begin!
Thomas: has grown up without a father's influence. Without the model of being a man, he doesn't have the strongest sense of himself. Despite this he smart, capable and shows courage when it is needed. He can appreciate the absurdities in life and understands you can't take life too seriously.
Young Lando Calrissian
Assuming JJ Abrams chooses to tweak over thirty years of expanded universe lore instead of throwing it out the airlock, Lando's personality lends itself to a childhood without a father. By the time he reached Cloud City, Calrissian had rewritten his own history so frequently even the Empire couldn't fully separate fact from fiction. His take on life is very blasé but he's shown courage if the occasion calls for it.