In case anyone is still looking at this thread: what I notice from tobacco that bothers me is that right from when I start smoking I feel a kind of coating on my tongue and roof of my mouth. This feeling of a “coating” must be an immediate reaction. I don’t get this with Peterson Flake or Pete’s Navy Rolls. I do get this feeling from a lot of tobaccos, including anything dark fired.
It'll be a long process figuring it all out, but you'll get there. Just stick to trying one blend at a time and make note of which ones bother you and which ones don't, and eventually you'll start seeing some commonalities in the base tobaccos for blends that bother your mouth and put the puzzle all together.