If you are looking at going unholy, you could give this a shot:
http://www.wowhead.com/?talent=jfcMMZZfMbhxcogcq0csut
some people feel like unholy is a 'tanking' build, whatever that is. With a build deep in unholy, it really strengthens your diseases. It will not matter if it one mob or many, unholy will add some nice damage. As soon as you get enough runic power, hit unholy blight, keep it up as long as you are in combat. if you plan on going unholy, i would also recommend getting the glyph of arthiric binding. it costs 30 venture coins.
There are two things I would suggest that are not talent related. They are both profession related. Either get herbalism for the 2k HOT, or max out your skinning for the bonus to crit. The other thing i would recommend is maxing out your mining skill. this will do two things. You can sell the ore and make a nice profit and you can get your own mats for gear if you know a blacksmith for any of the titansteel items. Farm the mats early, that way, by the time you hit 80, you will be ahead of the power curve.