I don’t consider it a “head start” to plant seeds in the fall — I consider winter to be my other main growing season. Things grow slower in winter, but it’s also soooooooo much easier to grow winter crops.
First: My summers are hot and arid. My winters are cool, but not terribly cold (nighttime temperatures are usually between 20-40 degrees, daytime temperatures are usually between 50-80 degrees, and it usually drops down to 7 degrees for the coldest one or two nights in February). We get almost all of our water in the winter. So winter crops don’t need to be watered.
Second: Insects hibernate during the winter. So winter crops don’t have any bugs on them.
Third: Bindweed is dormant during the winter. So winter crops don’t need to be weeded.
Fourth: Winter crops taste really sweet and delicious.
The only downside to growing in the winter is that plants grow more slowly. You can speed their growth up by adding some kind of nighttime protection like a hoop house, if you like; I don’t usually bother.
These are the food plants I prefer to plant in fall: my most cold hardy peas (Austrian winter peas are a good place to start), my most cold hardy fava beans, garlic, lettuce, blue mustard, shepherd’s purse, miner’s lettuce, winter wheat, daikon radishes, and every Brassica olerecea, napus, and rapa I can get my hands on. (This includes rutabaga, turnip, canola, cabbage, kale, kohlrabi, perennial kale, brussels sprouts, cauliflower, broccoli, collard greens — whatever I can find, basically. My plan is to eventually develop a thriving population of delicious perennial forms of all three species that can cross as much as they want to. I do not care what they were originally labeled as — I only care if they’re vigorous, perennial, and tasty.
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Lots of biennials are best planted in spring and harvested in winter, such as carrots and beets — but sometimes you can plant them in the fall instead. You won’t get a very big root to dig up and eat, but if what you want is to get them to overwinter and make seeds instead, planting in the fall can work great.
There are also the perennials to eat in winter. My walking onions, chives, black hollyhocks, and common mallow (all entirely edible!) are perennial evergreens that do most of their growing in the winter. My Jerusalem artichokes taste best harvested in December through February (they grow through the summer, and are delightfully drought tolerant, but the food they make tastes best when harvested in winter). The same goes for edible bulbs that make spring flowers (like tulips, brodeia, and camas).
And do I even need to mention garlic? Garlic cloves are always planted in fall, because they grow through the winter, and they are usually harvested in June. Or . . . if you’re lazy . . . you can just leave them in the ground and let them turn into a great big colony of garlic instead. Garlic’s a perennial! You can just leave it in the ground if you want to — it’ll come back bigger the next year!
I usually plant my least hardy peas and fava beans in January or February, and they start growing by around mid-February. I have separate winter and spring landraces for both species right now. But I’m trying to nudge them towards eventually having just one landrace per species, which is planted in fall. 
I’m going to be trying lentils, garbanzo beans, mache, chickweed, and maca for the first time this year. It would be nice if they take and produce well, but if they don’t, no biggie. I have enough winter crops to grow plenty of food with the species I’m using already.
In general, if you want ideas for more winter crops to plant in fall, these terms are each a gigantic clue:
a) “cover crop”
b) “winter annual”
In general, anything edible with one of those labels will probably make a good winter crop.
And be sure to look around your neighborhood at everything that grows as a weed in the winter. Look up what it is. Find out if it’s edible. If it is, give it a taste and see if you like it. Three of my favorite winter crops (common mallow, blue mustard, and shepherd’s purse) originally volunteered in my yard as winter annual weeds. Now I grow them on purpose. Yay! 