Just my opinion, so take with a side-order of skepticism.
New weapons, start
here.
I would have spec'd
like this for solo/questing (note, for a PvE realm, for a PvP realm you'd need to move a few points). I ended up going for Initiative (not Prep) but many people swear by Prep for similar builds, so... up to you.
For soloing it's proven to be better to use WP/WP. DP is pointless as mobs die too fast and you won't need Envenom. In groups you'll want IP on the faster of your two weapons and DP on the slower (for use with Envenom). Which hand is which doesn't really matter until end-game but you'll likely not find anything faster than 1.7 until then anyway.
Soloing with 2 1.8 speed weapons is fine. Ideally for raid you would want fast/fast, for PvP slow/slow. But for questing just grab the highest damage weapon you can get. At level cap, re-evaluate.
Cheap Shot, Mutilate, Mutilate, Evis, loot, stealth, next target....
I believe that the WP debuff is counted toward the Mutilate bonus, but that reminds me about some tests I forgot to run.... easy enough to test with Recount, I just never got around to it.
Good luck out there!