I suffer lots of damage to plants because of snails

You could try the new-ish organic slug pellets that contain ferric phosphate. They're supposed to be safe and not poison frogs, toads, birds etc.

Otherwise I think it's just trial and error - combined with going out in the evening at night with a torch to pick off the slugs and snails and stamp on them.

There are plants in your list that get eaten in my garden, so it probably depends how hungry your local slugs are. They eat day lilies, irises and phlox here.

Have you tried beer traps? You might have a few party frogs, but it does work for drowning snails.

I would leave boards, or rolled up newspapers out at night. Early in the morning, the critters will hide under them to avoid the daylight, and you can get up late, and scoop them up and bin them. It won't eliminate them, but a few weeks of doing this will reduce damage drastically.