I wouldn't worry about Epidemic. In fact, I'd probably stick to Frost/Blood and steer clear of the Unholy tree. Probably something like
this.
PvP gets pretty hectic, and it's hard to keep 2 diseases up on your targets. And at your gear level, your Howling Blast is going to be one of your heaviest hitters. So use the Glyph of HB, and let HB apply Frost Fever to your targets. Trust me, HB glyph makes it 10x's easier to apply FF, and it does it to multiple targets. And with Chilblains, they are now all snared, too. And since you'll HB (and therefore re-apply FF) so often you won't need Epidemic anyway.
Your Obliterate should be hitting for a decent amount of dmg, as well. And with the Glyph of Obliterate, you won't miss the bonus dmg from not having a 2nd disease on the target. Plus, with a single disease rotation (actually it's more of a priority system at this point), you'll get more Obliterates off, which is a much better use of those Unholy runes than Plague strikes.
I'd definitely max out Bladed Armor. At your gear level, it is a very big source of AP, which is what all of our spells and abilities scale off of. 2H Weapon Spec and Dark Conviction (5% crit chance) are very good, since you want to make every hit count in PvP. The points in Rune Tap and Imp. Rune Tap are optional, but could come in handy in PvP situations.
You'll want to make a macro to tie Deathchill to HB. A guaranteed HB crit every 2 mins is very nice. You only have to hit the button once, since Deathchill is not on the global cooldown.
Quote:
#showtooltip Howling Blast
/cast Deathchill
/cast Howling Blast
Also, you might want to look at the Power Auras add-on, or something similar to monitor Rime and Killing Machine Procs, so that none of them go to waste. I use Power Auras myself, and it works very well for keeping track of those things.
Icebound fortitude is great against stuns, Lichborne is used for breaking Fear. It not only makes you immune, but it breaks you out of fear, as well. And don't be afraid to use Unbreakable Armor as an offensive weapon, either. Pop it for 20 seconds of 10% additional strength, and summon your ghoul then, too. Your ghoul takes a snapshot of your stats when you summon him, so he'll get the extra 10% strength, too.
Here's the basic "rotation" to start with. I'd try it out a bit in PvE for a while, until you get used to it. And remember that you'll almost never be able to use an actual rotation in PvP.
Quote:
1st rotation: Howling Blast > Obliterate > Blood Strike > Blood Strike > Frost Strike (until you're out of Runic Power)
2nd rotation: Obliterate > Obliterate > Obliterate > Frost strikes
Save your Rime procs until your Runic Dump/Frost Strike phase, and try and time them with a Killing Machine proc, if possible. Also, if Rime doesn't proc, and your Frost Fever is about to drop off, Howling Blast. Always make sure you keep Frost Fever on your target, to take advantage of Glacier Rot and Tundra Stalker.