It's a bit difficult to point on "the one", as there is so much tobacco and i probably just tried about 3%....so far, but if I can mention 3 "desert island" tobaccos it must be:
Capstan Orignial (blue) for several reasons. It has a history and soul, it has good amount of nicotine, it tastes pure with something interesting in there, it burns perfect and never bites. I have never stored it, but I am sure it will age like single malt.
Three Nuns. I have never tasted the old version. Not from the 90's not from the 70' not from the 30's but the one they make now tastes sooo good I will not think too much about it. It is nicely packet, smells strong and is perfect what comes to nicotine. As I only smoke after food, and inhale and like it, i prefere my tobacco strong and full. It also has the soul and mythical aura that gives me a feeling of history when I smoke it. The only drawback is that it seems to dry out too quickly after opened.
Davidoff Flake Medallions is probably the only tobacco with black cavendish I really like. It must be the most exclusive looking, feeling, tasting tobacco I've tried.
I can mention alot of others like Scottish Flake, Royal Yacht, Orlik, Irish Oak, University Flake, Irish Flake. I hve not had the chance to try any of the american tobaccos, wich I really want, but they are impossible to get here. I have some plans how to fix it though so maybe I change my list later on.