If you’ll be printing lists of transactions from YNAB — either hardcopy prints or PDFs — the Printing Improvements setting should prove useful.
The main difference offered with Printing Improvements is the removal of the header row with category titles (section 2, highlighted in yellow in the image below).
But in addition to removing the header row, the Printing Improvements setting also spreads out the title row (section 1, highlighted in purple) and reduces the padding space between each listed transaction (section 3, highlighted in green).
My aging eyes generally prefer space between rows and columns but I find the Toolkit’s Printing Improvements layout to be very well considered and a huge improvement over YNAB’s default layout for printed content. Personally, I don’t print from YNAB often — I prefer to pull data out in CSV format for use in spreadsheets or text documents — so this isn’t a setting I use much, but I appreciate that it’s available.