Yeah, read that book a while back and made me look in my bookcase to find it again.
Found "The joy of UX" by David Platt right next to it ...... 
Here's the online version if you don't have it or just want to browse:
https://www.academia.edu/37156809/The_Joy_of_UX_-_David_Platt
BTW
For "EliveLight" theme I'll wait around till you've finished "EliveDark" and make changes to have consistency between the two.
There will be small differences in look.
- like I plan to keep the round icons (albeit with more space around them)
- They will be flat and reminiscent of Stable's E17 too.
- Have them in the same functions, color scheme and order as in EliveDark with the same highlighting mode.
- I'll rebrand current "Elive-GTK-light" to "EliveLight" and create a separate github repository for it, once done. GTK-light will remain a separate theme entity.
Suggestion:
Change the menu corners on the default cairo-dock to not have rounded corners to make it consistent with e16 menu.