Well, 60%. The best, reasonably fast one has around 50%. x)
As for this deck, I'd say the problem is being slow. You're trying to do too many things at once, many which aren't necessary to win most matches. Try to decide a direction and get it down under 40 cards by cutting out everything non-essential. It certainly looks heavily inspired by the old standard stallbow. A quick look at CCYB (
http://elementscommunity.org/forum/index.php/topic,9545.0.html) will tell you the same thing: success lies in focus.
For instance, Pulverizers for more lasting permanent control, Quint for the Golem for untouchable, growable damage, skipping most of the CC to cut down card amount drastically, and, of course, Permafrost and Antimatter for survivability. Nothing beats good ol' Permafrost. SoG's over Bonds for much faster and independent healing.. and that's about it. Speed is very important in a stall as well, funnily enough.
Good luck!