The question about how to sort authors and how to sort titles would be in addition to the questions about
: 1) interface language 2) library location 3) device choice 4) email delivery (for a kindle). It's the cumulative effect I worry about.
Having series prepended to titles by default for kindles may be worthwhile. Offhand I cannot think of any problems it should cause. The downside is that it would be surprising behavior, that will be hard to turn off. In my experience, you shouldn't do surprising things without confirmation from the user, it tends to generate a lot of noise from surprised users
