Rating: ★★
It was always a bit of a dubious proposition. Take one of the least interesting, least-amusing side-characters of Buffy and create a whole show around him? Even if you were aiming to capture the whole teenage-girl sex-appeal thing, it didn't really play -- Angel's whole thing was being mysterious and brooding, and it's just not possible to keep that up for a whole series.
So what did they do instead?
That's, uh, a good question. There never really seemed to be a coherent narrative to what was going on in Angel. There were, to be sure, story arcs, but they just seemed like... stuff. Weird, sometimes surreal, sometimes creepy family drama. Lots of girls for Angel to fall in love with, despite the way Buffy hung over it all, and of them only Darla actually made sense (until, of course, she became weirdly moral, like all the vampires the show lingers on for more than five seconds do). A few lacklustre apocalypses, a couple of underwhelming cameos, and plot threads that just sort of ended.
After building everything around Angel and Cordelia (who, by the way, was far better-written in Buffy), she drops out of Season 5 like, well, an actress who has had a baby and doesn't care to keep doing the same bad spinoff series. Spike turns up, incidentally undermining the whole dramatic arc of late Buffy, and does... nothing. Local talent 'Gun' develops from an uninteresting thug into an uninteresting thug with legal knowledge. About the only character who really changed during the show was Wesley.
For Buffyverse completionists only.