My personal favorites (in no particular order): Black Raspberry (my first flavor to ever order a 120ml jug of), Black Raspberry Lemonade, Black Raspberry Sweet Tea, Cherry, Cherry Danish, Cake (which I frequently vape 50:50 mixed with Black Raspberry)... And I love Grogg and Pear, but they're best together. 1 part Grogg to 3 parts Pear is my happy place. Apple Cider is also awesome with a bit of Grogg.
The most popular flavors seem to be House, Cake, Passionfruit, and some variation of Lemonade and Sweet Tea. Personally, you can't go wrong with Copper Creek. The only one I haven't tried is the Licorice (and I recently received a 6ml of that in a large trade, so it'll be tried soon ). She's a witch doctor ya know, so she has this stuff down to a science. Everything from her fruit flavors (my favorites) to her tobacco flavors (hubby's favorite) are spot on. And several new flavors will be making the site in the coming days as a new batch of beta testing flavors just went out. Pumpkin Pie has already made it to the site! I (obviously) have yet to try it, but I hear great things..