I'm the disorganized, disinterested one of the crowd....and I ABHOR paperwork.
I keep track of babies' feedings, and then only for a relatively short period. Once an animal is established here, I focus more on exceptions. Writing down, or otherwise documenting, that a snake eats when I offer it food seems silly - that's what they're supposed to do...and it was downright time consuming when I had a lot more critters. I think it's more important to be aware of unusual things; so when a solid feeder skips a meal, I notice. If it skips a second meal, I pay attention.
As far as breeding notes, I'm pretty outcome focused...I breed one male to a female (occasionally I might breed two similar males to the same female - ie I may put 2 different enchi males to the same girl). In any given season, I know what my goals are; so I know what I paired. I usually document witnessed copulations at least once - if the snakes don't separate before I can, in which case I'll take a pic of them together - that way I can reference pairings from previous years if I have a reason/desire to do so.