If you like simple DIY (with in many people's opinion...great results), you may want to try some of One Stop DIY Shop's "One Stop Flavors" and "One Stop Blends". They're concentrates that are made only for them, according to their specifications. They're ready to use singly in your own PG, VG, and nic base. Most ECF members who really like them, use between 6%-12% of any 1 of them in their eliquid. It varies though of course, with everyone's own personal tastes. Some use less and some use more.
My all-time favorites are the Lucky Shot, the Baked Cinnamon Roll, and the Lotta Latte. IMO, the Southern Sweet Tea, Pink Lemonade, and Strawberry Milk are also very good. I have quite a few others I haven't tried yet though, so my favorites may change! Mixing the Lucky Shot + Lotta Latte (about 5-6% of each)...is also extremely good! It was suggested to me by Kim, one of the OSDIY owners. I call it Caramel Latte since she had no name for it. It's been my main ADV for about 1.5 years now. Quite a few others here love it, too! In fact, if I'd discovered OSDIY's One Stop Flavors and One Stop Blends much earlier, I'd have probably not bought many of the 130+ other flavorings that I have from TFA, CAP, FA, etc.
OSDIY also has an on-going discount for ECF members. (Besides their "One Stop" flavorings mentioned above...they also carry TFA, CAP, FW, FA, and similar other name brand flavorings, too.) Using either the code ECF or JFK at Checkout will save you between 11-15% on your total order. They also have sales several times a year...usually 15% or more off.