Cass creep is a more solid deck, more consistent. On the other hand, I find de swarm deck more fun.
My suggestions would be:
Take these out
-2 azaleas
-1 lure
-2 soulshatter
-2 baronette (too situational)
-1/2 dark transformation (too expensive, but if you need more removal in your matches, you can leave one in)
Add these:
+1 ritual banishing (best removal you get)
+1 crescendo (amazing card altoghether, specially after you baited out some removals)
+1 grimwar
+2/3 black solus
Also, consider:
3 jaxi - amazing removal/dispel bait, and if you get it to stick, you can do amazing stuff with crescendo. If it doesn’t stick, there’s 2 deaths for you to watch
+1 shroud - shroud is just good 
2 shadow watcher: baits removal/dispel, and, if ignored, can wreak some havoc
Nightsorrow assassin - good in some MUs
Bloodtear alchemist and saberspine tiger are also some cards to consider