Shield Spear is trash, All your vanilla fiends + Mefist are trash, Skelesaurus is a gemini and Cerberus doesn't belong in competitive play, just to list a few problems.
In essence, the problem with the deck is that you feel like you've put together good cards that work together, but in reality you haven't.
For me this deck has no theme at all. What is the purpose insert cerberus when you only has 6 spell? Even base attack for cerberus is 1400. Which means, if you cant draw any spell card, that monster just wait to die. For me, using 3 copy of same monster is better compare using different monster . Plus, I also agree that you need to make deck with 20 cards only
If your main aim is to summon dark necrofear you may want to add 1-2 wonder ballons, send those fiend type monster to the graveyard, add a couple of dark mimic lv1 to your deck, remove the likes of skelesaurus and master kyonshee, metalmorph and golden apples and bazoo soul eater, what's the point of banishing monster with bazoo then you're trying to summon dark necrofear ?