I agree you could skip most of those if your only concern was the surface storyline. IMO though, all those episodes serve a metaphorical/thematic purpose on Buffy's journey. For example, Bad Eggs is all about sex because it's setting up the fact that Buffy's about to have sex with Angel. Now strictly speaking you don't have to know any plot fact in Bad Eggs to appreciate Surprise/Innocence, but thematically it's step along the way.