Food producing plants

Ditto the suggestion to grow herbs. Many are perennials (oregano, sage, mint, lemon balm, thyme, lovage).

Also you might consider Egyptian or "walking" onions. While they aren't really perennials, the tops form bulbets that get heavy enough to make the stalk bend over until the bulbets touch the ground and grow into new onions.

You can also grow chestnuts in zone 5 (they have the prickly casing).

You might also consider a variety of roses grown specifically for the rose hips (high in vitamin C).

We planted some pecan trees a year ago (we're zone 5b/6a) and while they're too young to produce, they haven't died yet. Most pecans are suited for warmer climates but you can find some that are hardy to zone 5.

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Our homestead-in-the-making: Palazzo Rospo
Eating the dream

when I sold my first 1 + 25 acre garden stead, I dug up the shrubs and trees I started there and moved them to my bigger homestead place.
That included crabapple trees, currant (fruit) bushes, cranberry, flowering crab (small fruit attracts songbirds), asparagus, rhubarb and a few others I can't recall offhand.

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The human spirit needs places where nature has not been rearranged by the hand of man.