I grew up using self-rising cornmeal mix (which I believe is about a 1:1 corn meal/flour ratio, plus baking powder), so that's what I still lean toward. Fat is generally bacon fat, if I have that around; if not, corn oil or vegetable or canola oil, whatever I have, and I have from time to time used olive oil.
I never measure anything in cornbread; dump some cornmeal mix in a bowl, add an egg, the fat (which I have never added hot), and enough milk or buttermilk, whatever I have on hand (I have used half and half in a pinch) until it's thin enough. I can eyeball the right amounts for my 8-inch skillet, which makes plenty for two with enough left over for small recipe of chicken and dressing. Definitely yes on the hot skillet.
Add-ins: All the aforementioned, with the exception that I don't like jalapenos, but have used chipotle; for corn I usually use frozen corn, make the batter thicker, and fry it in patties/fritters for an arepa-type side, great with chili or posole. Love grated cheddar in it, or cotija. Another add-in I like is chopped broccoli. I also used to make, when the kids were little, a "tamale pie," which had ground beef cooked with "Mexican"-ish seasonings, a healthy layer of cheese, and cornbread batter with corn poured over the top.
The only instance in which I make a sweetened cornbread is rosemary cornbread that's more cakey (higher ratio of flour to meal) and designed to go with brunch-type dishes. A sweet taste ought not go with rosemary, but it does, somehow. Recipe here.
Oh, and cracklings. I've never had it with anything but pork cracklings, but I see no reason it shouldn't work with duck or chicken. There is NOTHING like a big pan of crackling cornbread with "new sorghum," i.e., sorghum molasses during the first couple of weeks after it's made, before it ages. With country style bacon or country ham, and stewed tomatoes. Feed me that and just go ahead and kill me now.
