I know some of the above mention sugar; has anybody tried brown sugar? I never have; that's the reason for using tomato products as I understand it -- to slightly moderate the heat and smooth the flavors -- but I thought I'd mention it.
A local cooking expert who professes to loathe cook-offs once revealed he had participated in one using alternative ingredients intended to mimic the usual ingredients in a chili recipe and came in second in the competition. His list of ingredients included fresh ground cumin and white pepper, fenugreek, grade one paprika, lovage root, sweet white vermouth (for deglazing), tamarind nectar, ginger, allspice, and cardamom. Other, more traditional ingredients were also listed. No, this was not a Cincinnati style chili cookoff!
He didn't offer much explanation and no quantities. Ginger and clove he said are in many commercial chili powder mixes; allspice is simply a substitute for clove. Tamarind nectar was substituted for brown sugar because it has less likelihood of scorching and sticking in a big pot on a propane cooker.
I tried adding some tamarind nectar to a pot of chili once but really overdid it. I'm sure everyone knows tamarind is a prominent flavor in Worcestershire sauce. I used about half of a 12 oz. can of Jumex Tamarind Nectar and it was too much; I'll probably only use a couple of ounces, maybe only a couple of tablespoons if I ever try it again.
On the other hand, although I was disappointed in the taste of the chili fresh off the stove, chili always improves when it's reheated and I had no problem finishing off the pot over the next several days