I'm not sure what you're looking for, if you want to keep it a natural woodland or more of a backyard with a woodsy feel. Growing up I spent a lot of time in the woods in your area. I remember ferns, ferns, and more ferns growing under the trees along with trilliums and a wintergreen groundcover in many areas. Wild berries attracted birds and I remember the squirrels loved the wild hazelnut bushes.

I'm involved in an identical project here in SE Tx. My 1/2 acre or so of backyard has been a good example of the Big Thicket. This past month I have started cutting down dense brush, huge tangled vines, blackberries, and tons of poison ivy. I've cleared an area for a future shed and a separate seating area under the trees, leaving select native bushes and plants. In the seating area I will also be planting some free flowing flower beds using as many native species as I can find. On the outskirts of the yard I want trails meandering through the remaining woods with a few benches in small clearings. So the woods there will be cut back and cleaned up but not cleared. I plan on removing a lot of the blackberries and other brush and vines but not all. They attract the birds and rabbits and provide shelter. But at the moment they are so dense you can't see anything. Some areas are walls of solid vegetation-everything running together. Since I'm working by myself by hand, I think this project is going to be years in the making.

You've done a great thing!

I hope you keep it up. I am no expert on the subject, but I can tell you that if you had heavy buckthorn, you are going to get resprouts, probably a great carpet of them. Buckthorn control will take a couple of years. I'd recommend not spending a lot of money on planting yet. Let the first big crop come and treat it. (Roundup may be your best option. Fire is another, if you have the matrix to carry it, but not so appropriate for maple woods - it would probably kill the smaller trees.) I think you'll want to this for at least one year until that huge seedbed peters out. Then seed the area. Even after seeding, you'll have to do resprout control, but you'll get the upper hand eventually.

Directions here:
http://www.dnr.state.mn.us/invasives/terrestrialplants/woody/buckthorn/control.html

The Tallgrass Prairie Restoration Handbook by Stephen Packard may also be a useful resource at least for the control part -- The restoration part is heavily focused on oak ecosystems.

I was not able to find much online about maple forest, except one very interesting link about recreating a maple beech forest in Toronto. It gives you some thoughts about what to plant.

Here's the plant list they used:

Many native plants are already part of our Maple-Beech model, a model chosen because it was one of the GTA's major forest types. Our plants include many spring ephemerals: (Bloodroot, Sanguinaria canadensis; White Trillium, Trillium grandiflorum); herbaceous species (Red Baneberry, Actaea rubra; Jewelweed, Impatiens copensis); ferns (American Maidenhair, Adiantum pedatum; Cinnamon fern, Osmunda cinnamomea); as well as tree species. Three of the trees we want to point out are the Flowering Dogwood (Cornus florida), Shagbark Hickory (Carya ovata) and Common Witch-Hazel (Hamamelis virginiana). These are important to us as representatives of the Beech-Maple forest.

http://env.chass.utoronto.ca/env200y/zoowoods/text.html

Hope that gives you a starting point. The Wisconsin DNR has a list of native plant providers. They should be able to guide you further and may even have a mix for your kind of woods.

http://dnr.wi.gov/org/water/wm/dsfm/shore/documents/nativeplants.pdf

Thanks for your small act of heroism...

There is a company called Wildlife Nurseries Inc. in Oskosh, Wisconson from which I have purchased quality native plants and seeds and they were friendly on the phone so you might want to call them, get some advice and buy something from them. They don't have a website but their plants and seeds are good. Their number is 920/231-3780. Since they are based in your State their plants should be much more likely to be adapted to your conditions. I agree you will probably have some follow up weeding to do. If you need something before the follow up weeding is done I would go with whatever is cheap and easy and then after the follow up weeding go with your master plan.