Both Madoka and the Precure series are originals Magical Girls that can be watched and enjoyed by grown-ups. While Madoka is very dark and psychological, Fresh Precure is bright and colorful but has a really interesting plot and thus is not only for children.
Both anime start like your common Mahou Shoujo, with a girl meeting a magical creature and discovering that she can have magical powers ; but then it evolves to an elaborated story with unexpected turning of events. While in Madoka the change occurs suddenly at episode 3, it happens little by little in Fresh Precure, the heroines starting to understand that their task will be far more complicated than expected.
Also, in both anime, the characters are very appealing and we get attached to them easily, even to the enemies that are not always totally evil but more often tormented and confused.