Help deciding on Detonate Dead ascendancy, or finding some guides.

I have been in love with Detonate Dead conceptually since well back in my Diablo 2 days running a Corpse Explosion / Curse Necromancer, and this will be my first time playing the skill in PoE. I have always wanted to try it, either DD or one of its buddies - Volatile or Cremation - and have finally gotten around to giving it a try. I have about ~40 div saved up, and my goal is to have Simulacrum on farm as well as be able to complete other harder content that requires a bit more tankiness than my Hexblast Miner can provide with the investment I'm willing to throw at him. I want to try something new, and it's gonna be blowing up dead bodies one way or another. EDIT: Oh, worth mentioning that I am largely looking for a build that functions with CWC or COC Cyclone. I my love for Corpse Explosion is equal to my love for Whirlwind, and the combination is just perfect.

Elementalist, Occultist, Necromancer, they all seem to have some pretty solid advantages for the Corpse skills, and with the addition of the Forbidden jewels, it only makes the decision harder.

I already have an Elementalist, so I'd prefer one of the other two. Scaling Poison with Chaos Conversion on an Occultist seems strong, I'm curious what the Necromancer variations are like. Tanky first, damage second. If I can hit 10m or so DPS I will be fine I think.

I'm curious about any advice as to which Witch ascendancy to choose, as well as any guides (posts or videos) anyone can recommend. A lot of the content about it I'm finding is 3.19 or over 2 months old, and most of it is just a showcase with a PoB. My Google-fu isn't what it used to be, so I'm sure I've missed something somewhere. I'm more curious about the WHY Necro or Occu, versus how they perform I guess? What makes one stronger/weaker than the other in what respects?

Thanks in advance for any help.