All Poison Type Violet Team Build? (Story Mode)

I’m trying to do an all poison type run for my copy of Pokémon Violet (story mode not for competitive) but I’m unsure of whet the optimal team would be. I’m also playing with level caps so I can’t just over level and cheese the game.

Here’s my current team

Grafaiai (33): Unburden, EV Trained in speed and a bit of SPA

U-turn, Acid Spray, Poison Jab, Slash

Gengar (35): Cursed body, EV Trained in SPA and speed

Shadow Punch, Hypnosis, Curse, Hex (this move has been so useful for when my opponent is poisoned)

Vennonat (30): Tinted Lens, EV Trained a bit in speed

Poison Powder, Psybeam, Sleep Powder, BugBuzz

Toxtrixity (33): Punk Rock, EV Trained in SPA and speed

Toxic, Spark, Nuzzle, Tearfull Look

Mareanie (29): Merciless, EV Trained in Hp

Wide Guard, Poison Sting, Venoshock, Recover

Clodsire (30): Poison Point, EV Trained in SPD and a bit of Speed

Toxic Spikes (was this the right choice for such a slow moving Pokémon), Mudshot, Amnesia, Yawn  

I need help with what Pokémon would be best for the team as well as Tera Types, items, Moves, Nature’s, and EVs. For any team replacements (which is very welcome) just know that I don’t have the DLC so only main game Pokémon please!

My one rule is that Grafaiai stays because he’s my favorite Pokémon and one of the main reasons why I did this run in the first place.

Any help is appreciated! Thank you for reading!