Just finishing rewatching the whole series again, first time in over 8 years,
You have the source, Cole, the avatars, Zankou, saving Whyte, but the final storyline is that the sisters have to be punished because they want a normal life? A family, her husband back and not necessarily fight evil constantly etc?! I know it's the triad that has raised Christie, who has somehow managed to hoodwink Billie ( a very young Kaley Cuoco!) that this is a valid reason to go after them ?! And then the magical folk are also convinced as they aren't helping them anymore!
Unfortunately I feel like the last storyline was their weakest