What are Your Favorite Features

I've been using Photoshop for years at a very superficial level.  I'm now diving much deeper into it using and playing with masks, layers, brushes, patterns, etc.  What I've really discovered is that there is so much more to learn!

SO, in order to help learn more about Photoshop, I'm asking the community to let me know what features they like most if y'all have the time.

My favorites are the stauration/desaturation tool, the presence sliders, hsl color control, brushes and their mulitude of uses in all the tools,  layers, layered patterns and revealing them in different ways using the eraser brush, and a few more.  

For example, attached is a vacation photo where I've played with much of the above.  Yes, what is a monkey on my arem in Costa Rica.  I picked this as it was dull  (it may still be, it cerainly isn't subtle) and I wanted to see what I couls do with it.  I had a lot of fun and like the result.

If you have the time/inclination please share your favorite features!! I'm sure we could all learn a tremendous amount from each other's experience and responses.

Thanks to any and all who participate!!

Richard