I love me some siberian blackberries. I have yet to figure out how to eat ivy or foxglove.
Might not take off over here, but options available. In the UK our invasive species are: Grey Squirrel (cute, but not as cute as the indigenous red. Tasty bushcraft fodder), Himalayan Balsam (The internal nectar is edible, so maybe a high end energy drink?), Japanese Knotweed (Stems require half a day of soaking to get out the bitterness then can be eaten as asparagus apparently) and finally New Zealand flatworm (I guess if you can capture enough of them you can deep fry them as a kind of fritter, but probably not going to be many takers!)