My group has finally bumped up games from 1000 to 1500 points, so I was able to try out an idea I have been wanting to do to add ranged support to my Coven list, which looks like this at 1000 points:
(Prophets of Flesh)
I personally do not like building and painting vehicles, so have been limiting myself in my army lists. Dark Technomancer Reapers are clearly the go-to for Coven firepower, but I wanted to see whether some allied weapons platforms could substitute. I added the following 500 points to the above list:
(Expert Crafters/Masters of Concealment)
2 D-cannon Platforms
D-cannon support weapons are not looked on too fondly in Craftworld discussion because of the other options available in the codex, and their weaknesses involve a short range of 24" and susceptibility to melee. With 9th edition, I do feel like having D-cannon platforms included with Coven reduces these weaknesses. They do not require LoS and can utilize obscuring terrain, and their susceptibility to melee becomes much less of an issue when they are intermingled with Talos and Grotesques. The 24" range isn't as restrictive now that mid-board objectives are the victory conditions.
So I took 1500 points against Necrons and the support weapons performed very well, exactly as I had hoped. Expert Crafters allows a hit and wound reroll for each weapon, which is D3 shots, S12, -4AP, and D6 damage. At 70 points each, two platforms come in cheaper than a Reaper for similar firepower. Mine killed two Heavy Destroyers on turn 1, making their points back immediately. At toughness 5, 5 wounds, with a 3+ armor save thanks to Masters of Concealment, and a 1CP stratagem that gives them a 4+ invulnerable, I found them to be as resilient as my Coven.
This also allowed me to take Yncarne with my Coven, who performed admirably. She didn't take any fire due to the saturation of tough targets in my list, and added character sniping with Gaze of Ynnead. When one of the support weapons on a backfield objective was destroyed, she naturally teleported to the location and gave me the objective points the following turn. Support weapons are split up into separate units at the start of the game so one heavy support choice can become three teleport targets for the Yncarne. The rangers weren't too shabby, either, gaining a 3+ save and becoming lite-Mandrakes options for reserves.
I can still see some weaknesses compared to Reapers, with range being the main one. With the Coven units protecting them, however, I was able to comfortably move my platforms into the center of the table. Bring it Down is also a disaster because platforms are vehicles, and are easier to kill than a Talos or Raider. Still, I am quite hopeful about using more of them in the future to make an effective footslogging army.