1) Why do you have Fissure if you use Grave Effects (Mezuki, Plaguespreader, Dark Armed Dragon)?
2) As far as I can tell, 40% of your Extra Deck is useless. You can't summon Shooting Star, Formula or Puralis.
3) If you want to summon lv 8 synchros with lv 4 monsters I suggest you stick with Goblindberg and Summoner Monk.
4) If you really want to block your opponents attacks with Continuous Spells you should go with Fissure/Gravekeeper's Servant Lock...