If you're routinely having quanta problems, you could remove the chaos powers and replace with shards of wisdom, and then switch to an aether mark and dark pends (or vice versa, depending on what type of quanta you want first). That would make you even more vulnerable to CC, but it would also make you faster and more stable.
If you're biggest problem is CC, you could add some quints, though there's some big disadvantages there - not being able to TU quinted creatures is one, but it wouldn't really be that big a deal as long as you didn't quint all of your creatures, or just saved cards up when in the face of CC and then went on a vamp/TU/quint spree. If you add quints and switch to a SoW model, keep in mind that if you SoW after you quint, the vampires will start doing spell damage, which will bypass (most) shields but will also cause them to stop healing you.
Lastly, if I were playing this deck, I'd probably try to cram in some steals and/or drain lifes, but I'm overly attached to control cards, so that's your call really. Dusk mantle and/or stiletto are also possibilities.
