Sorry for the delay - I am all over the place. Sounds like you got a serious case of burnt tastebuds. If I can, I'd like to try to see if we can boost that CLS/CB for you to make it pop. I'd be willing to send you a bottle of flavoring only free of charge so you can drip the current bottles to taste if you would be willing to put in a small order...
Another piece of guidance that has worked for some other customers, is a small bit of citrus (if you have any lemon or lime vapes) will really help that vanilla pop more for you. One drop of lemon juice in a 15ml bottle will more than suffice.
I guess the bottom line is - I chase vapes. When the standard offering isn't working, I get after it and get creative. That's just what I do.
Lots to try if you are willing...