Another way to use a spreadsheet program that has become popular is to re-create 8-bit graphics from childhood video games and turn them into larger-than-life scenes. It‘s very simple to adjust the row and column height so that it becomes a perfect square, and most of the 8-bit games lacked any sort of definition, shading, or blending making them even easier to turn into spreadsheet art. There is also a huge market for this sort of thing. People that grew up with those types of games are now into adulthood, and many of them love to share things from their past with their children, nieces, nephews, and anyone else that cares about it. There is a certain amount of whimsy to these characters as well, and this type of classicism will never truly go out of style.
Well, let‘s take a look at your situation. What level are your athletes or clients at? New athletes or clients probably would not benefit from percentages as much as more advanced clients, as they need to learn how to perform the lift correctly first and foremost. Second, a new client will adapt to the exercise so fast that by the next time you perform the exercise, their 1 rep max may be out of date and thus their percentages would be incorrect (if they used to bench 100lbs, but after 2 workouts they can bench 110lbs, that 60% you have them working out as now too low to cause the adaptation you are looking for).