There are 2 flavors that I keep going back to over and over, and they have been in my daily rotation pretty much since I started vaping 3 years ago.
First is Virginia from Backwoods Brew. A bright golden flavor with a kiss of sweet. Use the code ECF10 for 10% off.
Backwoods Brew
The second is Morley from Want2Vape. A little rich with notes of sweet, nutty, and a hint of citrus from time to time.
Morley
These juices are nothing like one another. Sometimes I am in the mood for one, sometimes the other. They are both fantastic and fill the need for a straight tobacco experience without tasting anything like a cigarette. Way better than smoking ever could be. Also, they are both very easy on coils and will not gunk up for a long time. I can get up to 30 ml through a single atty/carto/coil before it starts tasting funky or burnt.
Lastly, I will throw in a recommendation for the Purity line of tobaccos from Heather's Heavenly Vapes. There are quite a few to choose from. They are all NETs, but they are easy on the equipment at the same time. I would look at Dark Horse, Dragon's Fire, Legend, Pirate's Booty, and Huntsman. All of these are pure tobacco bases with subtle distinguishing nuances. The flavored Purity NETs such as Gaia, Heavenly Army, and Shadow, are also great, but you said you were looking for straight tobacco flavor.
Naturally Extracted Tobacco : Heather