Guess the biggest is the walking and reading at the same time.
I noticed myself watching more and more fiction TV shows and found them too slow while being not dense enough and then I remembered I used to not watch anything and just read books in that time.
To solve that I found 2 way : - I challenge myself to read a book from each country/region on earth, often finding new themes I get passionate about. - I start buying every book from a given editor, also leading to great discovery / extending my horizon. (There should be a startup allowing me to subscribe to an editor :) )