Well first off when running Khorne Gore Pilgrims is auto-take. It gives you battleline and obligatory bloodsecrator, negates his main disadvantage (range of the buff), and negates the main disadvantage of slaughterpriests (unreliable prayer rolls). Flesh Hounds are actually a great choice but for summoning in rather than as part of the list.
I would add to Gore Pilgrims using Council of Blood with Skarbrand + WoK Thirster + Insensate Rage Thirster. WoK does run & charge (with +1 to them) while Insensate Rage gives charge re-rolls. Skarbrand may theoretically kill something, but really he is there because he takes choice away from your opponent; they HAVE to kill Skarbrand and you know it, so you know their strategy round 1 and potentially 2. Or they fail to realize that and Skarbrand just kills them, that's nice too.
The nice thing is you are getting free charge re-rolls from the insensate since the battalion lets him use his command ability point-free, you get one free run & charge from the WoK, and are starting with 3 points (1 normal + 2 from battalions) right off the bat so turn-1 charging with multiple thirsters is very possible, a good strategy to have up your sleeve if you get stuck with going first.