I used to love the idea of Daisy as an alt, but honestly I just don't see it happening. I would much rather her be her own character.
Here's my moveset idea. (NOTE: It says MarioEternal because that's my username on another site.)
B move and Down B move are from Mario Party.
Side B move and Up B move are flower moves that come from Mario Power Tennis and Mario Kart 7 & 8.
The Garden Trap Final Smash is original, but it is inspired by Daisy's special move in Mario Sports Mix and Daisy's flower powers.