there is really only a handful of things that are obscure enough to warrant a walkthrough:
1) during the day, the red ! over attractions can lead to discovering most of the Villains. they randomly appear. so keep checking map. visiting another attraction might make new ones appear as well.
2) Aurora sleeping strip&stroke is a Minigame, you need to jerk when she stirs, then continue. that leads to her naked outfit.
3) You need 2 million cash to unlock the rest of the world, via the red ! in the top left corner of the map screen. the final princess and the final 2 villains (as of 10/20/2022) are both unlocked after that
4) Helgas treasures are found by visiting a bunch of attractions around the maps during the day, the 4th one is found with Ariel
5) some content requires finishing princess's dates (during the day) to progress
6) if you get the Jessica Club early you wont be able to assign princesses to work there until you have gotten suggestions from Aurora or Belle to do Parades and Fireworks. after that the schedule will open up.