... I have to agree with dmaster. A decklist on a community forum really needs some solid info on play style, set information and such so that the community can help where possible.
I'd love to give my opinions on how to further strengthen your deck, but without knowing exactly how you want to play it, I'm afraid I'll be of little use to you. Also, an age division is helpful to know as there are different techs, deck lists, and all sorts of randomosity that gets encountered in different divisions.
Personally speaking of course I would cut 70%-90% of your pokemon for more trainers in general.
- Acanine
- Cofigirus
- Simisear
- Victini
-2 Whirlipede
So that is 19 Pokemon, the bulk of your list. The reason I'd cut that much out is simply because any deck that has a shot at being good really needs some sort of consistency. That said, you loose consistency by focusing on too many evolution lines, and that will loose you almost every game regardless if it's for fun or not.
So what to put in now? Trainers. And a whole lotta them.
Adding to Mora's suggestions:
+4 N
+4 Juniper
+2 Skyla
+3 Rare Candy
+2 Revive
+2 Switch
This will optimize your chances of pulling off and keeping keeping that poison status by forcing your opponent to either hit your bugs, or deck out in the process. Chances are that you won't need all the extra Pokémon at all.
Next up: Your already established Trainers. Since your deck would be more consistent you really won't need 4 Communications.
-2 Communication
This leaves room for any techs, but personally I like Ultra Ball for this deck list simply because it will speed up the rate you can play out your Venoshock abilities.
+2 Ultra Ball
Now that the bulk of the list is out of the way, we can work out the Energy count.
-7 Fire
-6 Psychic
This opens up 13 slots, so here you go:
+2 Double Colorless Energy
+3 Energy Switch
+1 Gold Potion
+1 Boufalant
+2 Bianca
+2 Mewtwo EX
I'll explain (Assuming you are in any division other than Masters). Energy Switch will move around energy to anything you want to attack with if you started setting something up and it's going to get KO'd soon if not the turn after. Putting energy on any of your bugs will make your opponent either want to play a Pokemon Catcher to get any of your poisoners out of the way or bring them up for the easy knockout, either way they will be inflicted by Poison.
Gold Potion is pretty useful here because it can take damage off when you may need it most.
Assuming you do go with any of my suggestions regarding the Ultra Ball, Bianca, or Cheren will help you get back some of the cards you lost.
As your main defense is a Psychic type, you want the Mewtwo for late game clean up or even for return KOs after some Poison damage. This is where Double Colorless comes in handy.
OPTIONAL:
+2 Shaymin EX
+2 Prism Energy
This is just a suggestion as far as Techs go. You may find yourself behind in prizes and Shaymin EXs Revenge Blast will deal 30 damage with an additional 30 for each prize your opponent takes.
