to removing all garbage from the title. I like my titles pure and neat. That includes series, numbering, and even the awful "___: A Novel" that they do.
Regarding series numbering, I believe
real series order goes according to internal chronology regardless of any specified ordering.
Some series' are just lumped all over the place.
I do, however, have a custom column called "Subseries" where I store information such as official series order when there are multiple series' in an extended universe. Riftworld, Forgotten Realms, Star Wars...