I grew about 40 butternut squashes last year. I probably ate about 4 of them in the form of soup (they do make a decent soup with a bit of smoked paprika or curry powder). The rest were given away or fùcked out the window.
Agree about sweet potatoes. Sweet potato fries make you feel like you're about to go into diabetic coma. Parsnips are great in a roast dinner when they're offset by other stuff, but not on their own.
You could make falafelly-type things out of beans?