In a comment on the last post, Dai from Lost and the Damned and Stunted (which I think involves heretics involved in car chases) expressed a desire for a list with Possessed. So here's an attempt.
Good budget HQ, and auto Warlord Trait to allow Possessed and maybe more to Infiltrate.
The main event. Alternatively, take 9 with Mark of Khorne or Mark of Slaanesh for net +1pt.
Sit on objective/quad gun.
10xCSM, 2xmelta, +CCWs, champion meltabombs
Midfield objective grabber, or infiltrating vehicle hunters.
5xSpawn, Mark of Nurgle
Tackle whatever the Possessed don't want to deal with. T6 to allow vindicator to drop near them with impunity.
6xWarp Talons, Mark of Slaanesh
Fast initiative 5 marine killers.
Annoying flyer thing, Long Fang etc. hunter.
Forgefiend - hades autocannons
Fire support, bust open transports for possessed/warp talons.
Vindicator, siege shield, combi-bolter, warpflame gargoyles
Shoot for termies/land raiders, big distraction to help possessed and spawn cross the field.
Aegis line with quad gun
Flyer support/distraction, cover for vehicles, extra shots vs. transports.
Due to the cost of Possessed and having no way to make them Troops, plus needing ways to handle the things that Possessed can't handle well (flyers, 2+ saves, vehicles in general) there's a lot of support and not much in the way of Troops. You could trade in a support unit like the Spawn for more Troops, but in general I don't think it's a big deal. One mission is Kill Points, so scoring doesn't matter. Scouring lets Fast score, giving you more scorers. Same with the Big Guns mission and your Heavy Support. One only has two objectives, one has one. So in only one of six missions will you necessarily be short on scoring units, and you still have several units that can help contest, and things that will punish anyone sitting around.
If you don't like the new things (heldrake, forgefiend) swap them for other stuff like terminators or havocs.
Hope you like it Dai, or that it gets your own ideas flowing!