Good question, but I think that for a more accurate comparison, one would have to compare season one of Angel with season four of Buffy. Nearly everyone (actors, writers, producers) on Angel had previously been on Buffy, giving them three more years experience from the get go than they had starting Buffy.
I agree that the first season of Angel seems better visually and at first glance, but the content and intentions of the first season of Buffy are so much richer; the concept of this girl in high school who bumps into the things that go bump in the night, how it deals with real issues in a non-confrontational way, everything in Buffy was a metaphor for something else, something I don't think Angel established untill very late (if at all) in the first season (the second had a handle on more in depth stuff).
Also, although Buffy was very much "monster of the week" at first, it still had a seasonal arch, and I felt like it was harder to secipher this in Angel.
~Kindred
