The best mode of organization will probably vary for each person due to personal preference, but the best way to do it in my opinion is to use tons of groups to simplify the appearance of code. So all the hero's code is in a 'hero' group, open that and there's 'movement', 'abilities', open that and there's a group for each ability.
I find this manner of organization to be very easy to work with even in sheets with thousands of events. Otherwise it can get overwhelming with so much code. Simplifying it this way makes it a cinch to instantly understand what code does what and to quickly find what you're looking for.