I’m now a full two years into using my variation of the Memindex/Bullet Journal on index cards and starting a third. I still find 4 x 6 inch index cards more freeing and flexible than using the more common notebook format. One big difference since a year ago: I’ve moved into using a significantly bigger box for increased storage which also includes lots of space for project notes, my zettelkasten / commonplace book practice, and an index for all of it.
I sometimes use one of the four typewriters behind my desk for logging. (Another benefit of using cards.) I put in a new card in the morning and add/cross out as I go throughout the day. I often use one of the other typewriters to write out slightly longer mini-diary entries about particular things as I go. This helps me get away from computer screens, even if it’s only for short breaks throughout the day.
Happy to answer any questions people have about the practice. (Prior AMA here.)