1.) Is it extreme?
(World’s Largest.)
2.) Friendly to new users.
3.) Already a proven idea.
4.) If you can’t already visualize the Title and Thumbnail, don’t start.
Action in thumbnail.
Simple, 3 elements.
Edit for the algorythm.
Open with clips of the sizzle. Fast paced.
Add in underlying story / wholesome surprise.
Youtube moving to “Viewer Satisfaction.”
Title under 55 characters.
You can autoswitch thumbnails for popularity using
Tubebuddy A/B Testing
https://www.tubebuddy.com/