I always go for all organic. Very rarely do I deter. Usually only for fruit that I love and can't get good in organic, and only if it has a thick skin. Melons mostly. In Florida, I get Mamey sapote that's local, but not organic.
Foods I would simply pass on if there is no organic option due to pesticide levels, aka glyphosate:
Berries
Grapes
Apples
Lettuce
Oats
Corn
Rice
And if you eat wheat, always organic, prefferably imported from Europe.