Poisonburst acolyte of chauyla is fun. Purple flames and hidden node for acolye of chayula give really nice chaos dmg scaling. Plus monk has an extremely good starting area for almost any build

Can’t go wrong with poisonburst arrow Pathfinder. People who play more of the game than I do would probably tell you monk is the stronger poisonburst arrow class but my Pathfinder cleans maps like a mop

https://www.reddit.com/r/pathofexile2builds/s/QKm13D9a7x

Liminal Coil Poison Pathfinder

Gas grenade Pathfinder is fun

You could do Shieldwall poison/bleed, bow poison, crossbow poison with gas grenade and whatever else. All these can get to a point where they can 1 shot/kill everything in the game pretty easily.

Several different ascendencies to pick from. Titan, Acolyte monk, Lich, Pathfinder, Gemling etc.

You are not really locked into a specific asc. Im playing a bleed+poison+ignite Infernalist right now which can oneshot pretty much anything in the game so as long as the ascendency has some synergy it can work.