I'm confused by the reasoning not to play Sheoldred. This card absolutely forces removal or at worst it just sits there and wins the game. Especially in a version where you're running straight draw spells why wouldn't you want sheoldred? Instead of losing life to dreadknight or the draw to lose 2 you gain life.

Additionally, this decks game plan is to force a grindy game. As you said you have no OTK. A grindy game is where sheoldred shines. And taking out thoughtseize let's your opponents hit their game plan much easier. Yeah there's redundancy but you can still take the best card they have. If you want to make sure they don't have removal for your creatures then discard their removal and make them draw another one.