I play a fair number of armies, but I figure Drukhari is one of the nonconventional builds due to the Raiding Force rules.
So I've been watching 9th rules through a Drukhari lens more than any of the other armies I play. Today gave me a shudder due to the detachment limit based on game size. So that's kinda what I'm going to throw in first.
At Strike Force Level (2K), we're allowed 3 detachments; if all three are patrols, we can have all three aspects of the army represented. Since Patrol is a Core Detachment, and one of our 3 patrols will contain our warlord, meaning we only pay for two of the three. We have been told that the raiding force special rule will still apply, meaning we would ALSO get 4 CP, because it is related to our special ability, rather than the shared detachment rules.
We do not know what a Patrol detachment costs. If a Battalion costs 3 CP, patrol will be less. If it costs 2, our +4 bonus offsets the cost of the additional two detachments so we break even. If Patrols only cost one, we actually GAIN +2CP!
However, this news also contains some downsides.
At Combat Patrol (500) we only get 1 detachment and at Incursion (1k) we get 2. So at 500, play 1/3 of our army. At 1k, play 2/3.
And even at 2k, though it's the "sweet spot," it is still problematic if you want more than 2 elites, fast attack or heavy choices that are specifically <Coven>, <Cult> or <Kabal> key words. Want 3 Talos? Well, that means you either exclude your Cult Detachment or your Kabal Detachment in order to take an extra Coven Patrol for that third Talos. You'll still qualify for the +4 CP bonus, so you'll still get the full 12 CP, but one third of your army is missing.
If they solve the problem by decoupling obsessions to detachments, and just say "All <Coven> units get the <Coven> Obsession regardless of which detachment they are in," that's okay. But if they try and fixing it by making each of our subfactions pick from one list, I'm not going to be happy.
And finally, on a minimum sized Combat Patrol table, Red Grief Reavers can hit anywhere on the board. A big unit of Reavers that just goes in and out of LOS blocking cover using Fly-by Attack every turn- you might be able to keep them hidden the entire game.
Anyway, what aspects of 9th have you seen so far that may have a huge impact on us?