This is my leaguestarter which I've spend too much time on. Ideas and critique welcome. I wanted to do something different but yet something that will work. This build is on the glass cannon side but managed to level up to 99 without 5-ways. I would not recommend this exact build for poison spark, occultist offers so much more but I like speed. I think raider is pretty okey though because of more projectile speed mastery is near and we can use master toxicist forbidden jewels. Some core pieces this build needs:

Oscillating sceptre (or body armour with elemental overload)
Glorious vanity with wither chance and chaos leech. Will feel like shit without.
Ashes obviously
Mana reservation efficiency if you want any kind of balance for dps and survivability
Cluster jewels and cast speed rings for dps
hands of high templar with despair/temp chains and other good implicitis. These gloves offer way too much imho.

https://pastebin.com/3FtPJb8L

edit: short video https://vimeo.com/731014779