I have but one piece of advise, ok, maybe two. First, add seasonings, a little at a time. You can always add more of something. But if it's in the pot, you can't take it out. I once added a bunch of cilantro to a batch of chili. Now cilantro in chili is a good thing. But too much cilantro gives the flavor of soap, not good in anything.
Tip 2. My last batch of chili included an ingredient that I'd never used before in a red chili, baking soda, just a pinch. Tomato adds acidity, and acids are sour. My chili was always good, but often had too much tomato flavor. That strong tomato flavor tended to mask the other flavors. I'd heard on DC, that the addition of a pinch of baking powder to marinara can enhance the sauce. I figured that it removed some of the acidity from the sauce. I tried it in my chili. The result was amazing. The other flavors, the peppers, the herbs and spices, even the beef flavor came through loud and clear, with just enough tomato flavor to carry the other ingredients. But you only need a pinch. too much can ruin the chili.
As was said by others, cocoa adds depth, as do the use of different kinds of dried and fresh peppers. Onion is a must, and not onion powder, but fresh slices. Cilantro, and coriander may be from the same plant, but have different flavors, and so both can add to the chili flavor. Cumin is a must. For beans, it depends on where you live whether you use them or not, and if you do use them, the kind of beans used is regional as well. A combination of dark-red kidney beans, pinto beans, and maybe black beans is an awesome mix, as each has a different flavor, again creating depth of flavor.
Use what you know about cooking, and you know a lot. Choose your ingredients by what you know. Play with the flavors in your mind before adding them to the chili, and then, add them a little at a time, let them cook in, and taste. If you need more of something, you can add it. Tweak it as you cook it. Chill it in a bowl full of ice water and refrigerate over night to really let the flavors blend. Reheat to 160, and hold at 145 to serve. My favorite cheese to go with chili is sharp cheddar, but that's just me. Queso Fresco is also very good, or Monteray Jack. Even a good Colby, or sharp Pinconning is very good. The cheese must accent the chili, not overwhelm it.
PRiFy, you will make the best chili, period. How can anyone else hope to compete?
Go git-em.
Seeeeeeya; Chief Longwind of the North
I will vote pintos! 
