This is a really great recipe. A wide range of flavor profiles to create a satisfying vape experience. Sour, sweet, bitter, tart. The FA black currant is rather bright and bitter, but provides an additional level of dark berry that pairs with the FW blueberry very well.
Though the TFA sweetener does a sufficient job of bringing down the bitterness of the FA black currant, I found myself instead wanting to offset this with a nice bright berry, such as TFA Wild Blueberry or TFA Strawberry Ripe. This would help cut the bitterness of the black currant without cutting back the lemonade flavoring which seems sensitive to sweetener.
On a side note, I mixed a side batch with INW Black currant and it's a much more mild black currant with subtle creamy texture. It kinda strayed from lemonade, but is super delicious and adds an extra component to the recipe while keeping everything in balance.