My main concern is the super fragile vampires. While playing around with them, even with 3-4 cloaks, they can be quite vulnerable since you won't draw the cloaks in time. Do you often get outrushed? I feel that it looks like it'll lose to a fast rush.
When you put out only one or two, since vampire army isn't too strong at that time, the opponent probably would expect a stronger creature and hold the CC in hand.
When you get what you need, you can start chaining cloak and use SoP
I think this is his strategy
Of course CC is a problem since Vampires get not Def Boost. You might counter this with adding one or two Gargoyles or using only Gargoyles and Liquid Shadow, though this would require a completely new build.
However, waterxz is correct. I usually don't play anything except pillars the first few turns, hardly depending on the enemies strength. If possible you should play cloak, SoP and Vampires while chaining Sundials. Otherwise, chain Sundials and follow with SoP, Cloaks and Vampires later. When you built up enough power or you have to stop your sundial, remove SoP and atk. You might want to restart the chain later together with another SoP because you have more vampires now.
Indeed, sometimes it's very tight on quanta. So maybe remove one SoF for another tower. You should have enough draw power to still get one while powering your vamps.