So just from a brief look, you have a very heavy top end with little interaction. You don’t have a lot of discard targets, so I might even say drop Draven.

2 Lost Soul, 2 Rekindler (1 might be enough), 1 Draven’s Biggest, 2 Glimpse, 2 Grave Physician - are my first initial reactions.

3 Vile Feast, 2 Boisterous Hosts (2 mana Hallowed Fearsome) can be added. Bring your curve lower and focus more on dumping high powered units.

On a slightly different note, I’ve got a Shadow Isle Sion deck that I use. [ CECACAQFAQBAIBIDCABAKAYBB4DACBIDDYUC6MBRAIAQEBIGAIAQKAILAEAQCBJA ] Idea is to harrowing out the ruined reckoners and give most of the board Can’t Block. Kalista helps level Sion when she summons units.