Either
-5x Julianos: Craftable, reliable, and offers good damage in all scenarios. Tends to perform best in unorganized groups. Not as high potential damage with Warhorn buff.
-5x Twice Born Star: When running trials with good Warhorn uptime TBS has the potential to perform better than Julianos. Use the Shadow as your second mundus.
-5x Scathing Mage: Tedious af to farm compared to BSW, but is basically required for Magicka Nightblades. High uptime due to Path being classed as direct damage, and offers the strongest stats.

-2x Grothdarr: Use this in vMA, Group Dungeons and Trials with no ranged damage dealer requirements. Highest performing monster set.
-2x Valkyn Skoria: Use this when you need to deal damage from range (out of Grothdarr aoe radius). Not as strong as Groth, but it procs on targets from a distance, allowing you to stay ranged.

-3x Minor Slayer jewellery: Best performing 3 piece set as of current meta, and will most likely stay that way coming into Morrowind. Moondancer is slightly better than Infallible Aether.
3x Willpower jewellery: Cheap and not bound like the Minor Slayer pieces are. Only downside is you cannot run Minor Slayer staves to good effect, you'd need 2 Maelstrom staves to utilize this set the most.

Sharpened Weapons: There is no other practical alternative. The extra spell penetration gained from this trait is so efficient for its slot that it is way too optimal to pass up in any case. It doesn't matter what you find in Sharpened, use non trait staff over precise Maelstrom or Minor Slayer. Sharpened non set outperforms any kind of precise weapon.

Fire+Lightning Staff: Use a Fire Staff on the front for Blockade of Fire and a higher overall dps, but also use a Lightning Staff on backbar to increase AoE damage during trash fights and give access to that cheesy heavy attack.