I think that Angel had plenty of standout epsiodes. Easily just as many as Buffy. They perhaps just don't get as much attention because they're not as gimmicky.
Season 1: Hero, I've Got You Under My Skin, Five By Five, To Shanshu in L.A.
Season 2: Are You Now Or Have You Ever Been?, Guise Will Be Guise, Darla, The Trial, Reunion, Redefinition, Reprise, Epiphany
Season 3: Billy, Lullaby, Birthday, Waiting In The Wings, Sleep Tight
Season 4: Spin The Bottle, Apocalypse Nowish, Orpheus, Home
Season 5: Life Of The Party, Lineage, Destiny, You're Welcome, Smile Time, A Hole In The World, Not Fade Away