Style over substance may be a common phrase but frequently CVs possess neither.
Layout
Inconsistencies make CVs difficult to scan read. Sure, it’s not going to be a work of art (unless you’re a designer of some sort, in which case it should be: show off your talents) but it should be set out neatly and consistently.
Fluff
Don’t over-generalize. If you’re applying for “Widget Developer” and you list “Widget development” under the responsibilities in your employment history, that doesn’t tell anyone anything.