i like how swanky is categorizing it, so i'll follow suit.
for me, the must-have classics are the reissue and the classic flap.
then, for work, my choice of structured tote is the cerf tote.
for casual wear, i like the square vintage ligne tote. for night or dressier times, a fun bag (for me, it's my lady braid satchel) like the ritz patent or the crackled patent flap.