I like using a strong menthol (Halo Sub Zero) mixed with sweet juices (like bubble gum or fruit or candy). My favorite menthol salt was Twist Mint 0 degree. I liked that one all by itself.
Current one is gummy bear. I used to make my own ejuice. It’s much cheaper that way, plus it was sort of fun coming up with my own flavor combinations. But I don’t think my grandparents would be happy with me trying to make ejuice in their house.