You will get a lot of different answers, but here is mine. When I cook brisket, I only trim the fat off of the top where I want the bark to form. Other than that, I leave the fat on during cooking. I cook it fat cap down.
As far as seasonings or cooker choice, the seasonings you listed sound good to me. Use what you like. As far as cooker, use the one that can hold the temp you need the longest without tending it.
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