Lately I have been using ground chicken instead of beef. I always start with a quart of home canned tomatoes and quart of home canned tomato juice, which taste way better than what you can buy at the store. Yes, I know how to do my own canning!
I have also found that the quality of the spices used makes a huge difference. The name brands you buy at the grocery stores (e.g. Tones or McCormick) tend to contain a lot of fillers and are not as flavorful as the organic spices you can buy at Whole Foods, Natural Grocers, or Trader Joe’s. Over the holidays I stumbled across a spice store in Tumacacori, Arizona which is about 20 miles north of the border south of Tucson. It’s called the Santa Cruz Chili & Spice Company, and they sell chili and other pepper spices with heat ratings ranging from mild to OMFG call the paramedics!
https://santacruzchili.com/online-products