If you like SF and Fantasy don't forget to hit the BAEN Free Library and FIFTH IMPERIUM Web sites. (Give you something to feed the PB360 with.)
Fonts? I favor Georgia (its part of the standard Windows load) in size 22 with wide margins and no status bar. I tweaked the styles to go with 99 space-before on Heading 1. Looks just like a well-formatted paperback.
Themes? I favor the FIVE theme. I use Century Schoolbook or Lucida as the System font and set the bookshelf to Easy view.
I set the rocker ring as:
right - next page
left - last page
up - next chapter
down - previous chapter
center button hold - status
Top flap - Note taking
Botton flap - TOC
That way I can do all the common reading functions with one finger.
Your milleage *will* vary.
Now git going!
(And no, its not a Cult. We're just well-informed.)
(Strictly a rational choice.)