Hi,
Dont take this as harsh criticism, but after playing a Lock a while and studying your setup, i find these tricks have helped me out a lot. (They may not necissarily all be to your tastes)
Some general tips that for yourself and others:
KEEP YOUR SCREEN CLEAN!
-Your timing demonic circle, soulburn and shadowward in 3 places (timers, action bar, and cd bar) your timing haunt in 4 (same + the debuff duration), are they all necissary?
-Your tracking the boss health in 3 different places (Excluding your target frame)
-Consider hiding keybinds your very used to and/or dont use frequently
-Having your pet bar out, and central isn't really necissary either - how often do you need to know when he's auto attacking?
-Consider using an addon to relocate where your heal spam is on your screen, again it just helps to keep things neat and see whats happening to and around your character. (ScrollingCombatText is good at this.)
-Replace Quartz. I know Quartz bar has been a long and favoured cast bar for a while, but it doesn't calculate channeled ticks with Haste. Gnosis does. When your drainsouling theres nothing worse than missing your tick because you have to recast all the time. And recast DS when you get Eradication proc.
-You mentioned you clip DoTs, you are supposed to clip ~3secs btw
SPELLCLEAVING!:
So, fights like Shannox allow us to exploit spellcleaving to the max, in the past we've seen fights liks V&T. My recommendation is to setup what i call a 'Dual-Targetting system'.
Here we utilize the /focus command and macros to the max! Heres an example:
/cast [mod:alt, target=focus] Unstable Affliction; Unstable Affliction
Normally it will cast UA at my target. If i hold Alt whilst pressing it it will cast UA at my /focus target without tabbing or losing target etc. It can save a lot of confusion and i recommend doing it with all/most your spells. -It will require using an effect DoT tracking system on both and some practice, but i find it a much more practical solution.
On the topic of macros, get yourself a /petattack macro. Pets in Firelands are stupid and wont attack unless you tell them to, so send them in early either by clicking it or macro'ing it!
I see your using the Razer Naga, thats good! A lot of people find it best to bind their most used spells to their mouse, I myself use it to spam SB/Inc and Haunt on my mousewheel up/down to minimise the effect of ms. Freeing your Left hand to always ensure you can move quickly is crucial, and keybinding so you can dps on the run is even better. Some of the things you've listed I already do such as /petattack macro's
GoodLuck with the rest of the Tier, and i hope this has been useful =]
M,