Maybe that in itself would be an interesting topic: What you can actually change about yourself. Can you change your appearance? Your tastes? Your personality?
Of course it is easier to change and measure short-term effects such as a change in habits. Do any other, similarily easy to measure short-term changes and benefits come to mind? Any of those would be suitable for a literature review.
Your review of spaced repetition falls in this category for example. You can change how you learn and this change, especially the change in what you retain can be measured and has been measured.
The last prize, for the best literature review of spaced repetition, was moderately successful, inspiring a pretty good review of the academic literature on spaced repetition. I am interested in experimenting more with prizes, but I would like to get input other people's input: what are other good topics for future prizes?
The topic should be: