It's hard to be certain what is what, because: 1) the diffs are subtle, b) there are many variables that (seem to?) overlap, and iii) there is a lot of randomness involved as well. So, once you get them into a fortress, it's absolute chaos to try to see any clear pattern.
So emphasize words like "seem" in the following... I'll do it only for the first one...
"Activity" seems to influence how much they work vs how many breaks they take.
Drinking ("over-indulge") seems to influence how long their drink breaks are and/or how often they take them, consuming more drinks/year on average.
"self-discipline/procrastination" might involve how long a dwarf takes to figure out what to do next - some have that "?" over them longer, and end up in the Meeting Zones when there is work to do, and others latch on to the next job right away.
"routines/change" might influence how a dwarf continues pursuing one type of labour vs. shifting between different possible labours - some seem to do the same thing over and over, and others seem to bounce around a lot more.
"Doesn't do more work than necessary & procrastination" vs "strives for perfection" This might influence whether a task is completed before any sort of break is taken. Or just the amount of work vs breaks? average quality? unclear, but it sounds bad enough.
Some dwarves clearly work longer than others before breaking, eating, drinking and/or sleeping - this is obvious whenever you get a large wave of migrants, and they do those activities in waves - at least at first. (Later those breaks seem to move further apart, and an averaging effect arrives over time.)
Many seem to deal with cracking under stress - tantrums, insanity, whatever. No work/task related.