It can take awhile. ;-)
I have 4-5 that I like and use regularly (as evidenced by 40 or so 50ml bottles of them)... and some that really shine in an rda/rba, but are only just "good" in a carto tank. One, MBV Solar Flare is pretty good in most anything.
I have one that is a mix of two that I love in most anything, but both the base juices require about 2-3 weeks of aging before they really come into their own.
Keep trying... when you find your "holy grail"... you can give away all the other stuff to new vapists.
Agreed!
You gotta remember that with an RBA you will be able to taste the juice better than in a carto. So pick your device accordingly then try different flavors.
Reversely, some flavors that may be too strong on an RBA may taste just right in a carto.
As for advice to find the "holy grail". I would check the ejuice section. Half of the great juices I use for EDV were recommendations from other people. Good luck!