When the episode first aired, I found it to be just okay. It wasn't bad but it wasn't great. It's not until repeated viewings of it that I've gained a greater appreciation for it.
It's also one of those episodes that make you wonder just how much did Joss plan out. You make an interesting point of bringing up episode 1x03 in comparision to this episode. Did Joss have an idea to have Willow struggle with magic that early in the series?
I think Buffy's birthdate is one of those errors that occur in Season One that are later "rewritten" to suit the Buffyverse mythology, such as Giles' past and Angel's back story. I mean one of the most memorable lines in the first season is Angel's line when he first meets Buffy: Truth is, I thought you'd be taller, or bigger muscles and all that. You're pretty spry, though.
Yet we find out later on that Angel has already seen Buffy and she's the reason why he's gone to Sunnydale in the first place.