The problem with your logic in Daisy moveset potential is:
Your suggestion for a basic spinoff moveset would be literally scraping the bottom of the barrel in moveset. Daisy has an identity that you don't seem to realize. Unlike Waluigi who just so happens to be Luigi's Wario, Daisy is more than just Luigi's peach both in terms of personality and abilities. She has been very well developed through the spinoffs to the point of arguably having more personality than Bowser Jr even. And she'd be useful to complete a character square existant in canon that has existed 3/4 since Melee.
Your suggestion for a basic spinoff moveset would be literally scraping the bottom of the barrel in moveset. Daisy has an identity that you don't seem to realize. Unlike Waluigi who just so happens to be Luigi's Wario, Daisy is more than just Luigi's peach both in terms of personality and abilities. She has been very well developed through the spinoffs to the point of arguably having more personality than Bowser Jr even. And she'd be useful to complete a character square existant in canon that has existed 3/4 since Melee.