The holes in the leaves look like capsid bug damage. Keep using the bio insecticide for flying pests like capsid bugs, white flies etc...
As for the slugs, copper and/or slug bait work well.
I've had problems with both as well. I mix my own spray for the insecticide. I use neem and pyrethrin soap.
Heres an old thread I posted about the Capsids
Capsid Carnage