There is my thoughts :
K. Command : as much as I love Rakdos cards, 2 is enough, maybe one more in SB
Anguish Unmaking : 2 is good I guess, 3 seems too much
Sorin, Solemn Visitor : if you want to use this card, you should build arround, you get much value with it by playing
Lingering Souls, maybe considering
Hero of BladeholdBrimaz, King of Oreskos : this is legendary, 4 seems way too much, I'd advice 2 of (getting slots for
Lingering Souls)
Sin Prodder : I don't think the card is needed there, or if you want to use it, take the burn way (add some
Lightning Helix). If you use it for draw engine, Painful Truth is better
Some manlands (Shambling Vents) instead of Ravland and maybe a
Vault of the Archangel, if you play some Lingering Soul
Hope I've been helpful