I like to combine goldfish-proof plants with edible decoys.

Java fern and anubias are both attractive and bullet-proof. The added
benefit is they can be grown on rocks or wood, so not only can you
shift things around wihtout disturbing root systems - you can remove
them entirely when cleaning the aquarium. Makes life a good deal
easier all round. They also don't need a lot of light.

Then I would add some hornwort and elodea (or whatever its new name
is) Should your fish feel the need for a salad they will go for these.
Both plants usually grow back and if they don't, well they are pretty
cheap to replace.

I find this technique pretty successful at protecting the "main event"
plants. I also think its nice for the fish to have something to nibble
on. Plant material is not going to lead to lover-feeding water quality
problems as its mostly roughage.