Hello. I'm working on my Frost DPS set/skills. Here's the wow-heroes link:

WoW Heroes - World of Warcraft PvE character info & ratings

It's not correct as i've upgraded to ilvl 245 T9 hands, the badge ring and i'm running with double Black Icicles with Fallen Crusader/Razorice.

Rawr puts me at 4340 dps on heroic dummy (ie only my horn & icy talons)
I manage to pull out a very stable 3400.

I'm guessing my failure is at my rotation. Here's mine:

IT, PS, BSx2, Obl, FS, Obl, FS, FS, Obl, Obl, Obl, FS dump, rinse repeat. Ofc i rime whenever it's up, preferably in place of a FS.

What am i doing wrong?