If you're starting from a blank slate, you might want to plant some fast growing hardwoods, like cottonwood, silver maple or hybrid poplar to give yourself a jump start to some larger trees. Granted, they aren't as good firewood producers, but they can pick up the initial slack while you're waiting for your other hardwoods to mature. Maple, Oak and Black Cherry were our preferred firewood sources back when I was growing up. Oak is great for all sorts of uses (lumber, fuel, food) but can take a while to mature. Plus, of
course there's any number of fruit trees (
apple, mulberry, cherry) that you could interplant. You could even plant a stand of bamboo for the goats, just be careful because bamboo can be invasive (although it can also be used as firewood if you're careful to break the cells - otherwise it's an explosive hazard).
As for understory, there's always berries (blue, black, rasp) and choke cherries. I'd plant a bunch of herbs, wildflowers and supporting plants as well. I'd probably try to include clover, cowpeas and chicory for the goats.
Just some thoughts. Good luck!