I started watching Angel parallel to Buffy’s fourth season, due to characters from both series occasionally turning up in the other series. Originally I watched the show for two or three season on TV, but never really got its appeal. The series concept is basically Angel doing good deeds in Los Angeles to atone for his evil past. What made me lose interest was that the series never developed its own identity beyond that gimmicky concept. That impression hasn’t changed on re-watching the show.
Angels needs a gimmicky seer to get to his next action, he’s still pining for Buffy all the time (which makes him more emo than he needs to be) and second-tier characters from Buffy get reused. Worst of all, the show gives the impression of meandering from plot token to plot token with no end in sight and the overall plot evolving from moment to moment with no real plan. Buffy managed to tell one big story in each season, with each season having a unique flavor of its own. All that the first season of Angel managed was ending with a cliffhanger and no real resolution to anything.
All that said, it’s actually not so bad if you don’t compare it to Buffy. Angel, despite mostly being a gloomy sort of fellow, is actually allowed to be funny on occasions. Those moments are true gold. And the slowly developing antagonists in the form of Wolfram & Hart were quite intriguing. And while the show really lacked memorable single episodes and overall anything memorable at all, it sort of grew on me. I dunno, not the best, not the worst, but at least fun to watch from start to finish most of the time.