I tend to be in-between on Angel as well -- I like his story quite a bit of the time, but am disinterested other times. I do too disagree with the idea that AtS was more adult/layered/mature/etc. Well, more adult, perhaps -- insofar as it dealt with a somewhat older period in one's life than BtVS did. But I personally still find BtVS still more...enlightening about life as a twentysomething than AtS, even if its ostensible focus was younger. But I do like AtS a lot (just less than BtVS).