In my opinion, if you are the only warlock in the raid, Raid Utility is more a a better use than trying to max out a tiny bit of dps to yourself then benefits to the raid.
For example, on most encouters im unsually pulling out 5-6.5k dps no problem, mana replenishment coming from the raid so my pet is never running out of mana, not even close.
in my personal talent build:
my warlock talent build
I bring full level of healthstones, definatly a lifesaver of for example Hodir/mimiron/vezax.
Also the Shadowfury is such an amazing raid utility. It can daze trash mobs going to XT-002. bomb bots on mimiron and assault bots. and adds on auriaya.
Soul link has been a life saver to me many times. Sonic Boom + a feral charge kills most low geared players, this prevents me ever dying. Tanking mimiron, Soul link is a must, so much damage bypassed is great help on healers.
Priorities list
1.Curse of doom (best to cast first as wasting GCD for incinerate to put up a dot is wasted DPS)
2.Immolate
3.Conflag (If glyphed which you should be)
4.Chaos Bolt (pew pew)
5.Incinerate filler
keep up Immolate and CoD when gone through the fight, ALWAYS proritize Conflag + Chaos Bolt over and Incinerate.