The biggest problem I have here is defining an aromatic, and apparently I'm not alone. This problem is made even more acute if I'm to take seriously GL Pease's assertion that virtually ALL tobaccos (even supposedly "pure" Vas) have some flavoring added to them. And that's not even getting into the question of whether Lakelands or English blends like 965, which has cavendish, are technically aros ... One could also be REALLY contrary and ask how latakia can be considered a natural tobacco flavor, since it's enhanced by the various spices that are added during the smoking/curing process, but perhaps that's carrying it a bit too far ....
That being said, I would agree with those who say there are some quality American aromatics on the market. Not many, perhaps, but they are out there. Autumn Evening is the first to leap to mind, but others have already pointed it out. Captain Cool by McLelland is basically a premium version of Capt. Black, and I gladly go through a tin every year or two.
Pennington Gap, Classic Burley Kake and Shortcut to Mushrooms are also superlative smokes, IMO. If you count some of the lightly flavored American-English blends as aros, then both Epiphany and Gatlin-Burley should probably be listed as top-shelf tobaccos. Haddo's Delight and Barbary Coast are (if I remember correctly) flavored with spirits, and many people believe that both the distinctive sweetness of the Frog Morton series as well as the famous "ketchup" signature attached to many McClellands blends are in fact the products of some kind of artificial flavoring (I don't believe that's the case, but since I have no way to know for sure I figured I'd throw it out there, as well, given the split opinions seen on TR).
In short, it seems to me there are a great many nice aros out there, at least so long as you stay away from stuff like Capt. Black. But even that is just my opinion, as many smokers really like stuff like 1Q and others (such as myself) really enjoyed them way back when we first picked up a pipe.