Alley and water imagery in Angel's storyline
I wrote this over on IMDb2, but it got lost amongst the more gossipy stuff...
Here's something I've always loved as a thematic thing in BtVS and AtS: alleys and rain/water are intentional constants in Angel's storyline.
Liam was sired in an alley. Several flashbacks have victims in alleys like Daniel on Christmas, Darla's streetwalker and Drusilla siring William (Angelus also later had a few alley showings with werewolf!Oz and spitting out Gage's blood). Angel couldn't feed from a Romanian woman in an alley right after getting his soul back. Angel hid the missionary family from Darla in an alley, which Dru sensed (Fool for Love-only viewers wouldn't know what Dru sensed or why Angel was with them post-ensoulment, with Darla 2x07 answering the questions in the next hour). Whistler found Angel in an alley trying to catch a rat. Buffy met Angel by kicking him down in an alley. Angel lost his soul in a rainy alley (Buffy and Angel had previously been in the ocean and ran through the rain). Angel saves girls in an alley in the opening scene of his show, while also struggling with temptation at the sight of blood (a deleted scene was censored where Angel tasted Tina's blood, jerked his fingers away and scrubbed his hands--the removal of this leaves a plothole with the opener and Doyle's comments about Buffy's blood leaving a bit of a craving). Angel saved Faith in a rainy alley. Syphilitic Darla attempts to get the 1992 mullet vampire to sire her in an alley and she reminds Angel where he was sired. Angel's epiphany in the rain echoed Innocence (Darla even quotes Buffy, saying "Was it me? Was I not good?", not unlike both saying "Close your eyes."). Darla died (she notes the alley theme) and Connor was born in the rainy alley behind Caritas (and of course, Holtz spares father and son--also note Fred holding Angel's jacket over her head, evoking major Virgin Mary imagery with the impossible conception/birth, which Wesley and Lilah have a conversation about later). The Beast arose in the same alley and started a rain of fire, which was occurring when Jasmine was conceived. Faith and Angelus' Orpheus mindwalk went into Angel's rat-eating past in an alley, which is where Angel and Angelus fought each other and Angel urged Faith to not give up. Angel's season 5 opener echoed the City of... opener with saving a girl in an alley, but with W&H intruding. AtS ended in a rainy alley facing the apocalypse.
Water is another thing that comes up a fair bit along with rain. Angel's watery coffin at the bottom of the ocean is a big one and Deep Down amps up the water imagery in the hallucinations. There are also the Buffy/Angel fight under the sprinklers in the mall and Angel saving Kate in the shower from her suicide attempt (and not having an invitation, making it another of his PtB miracles). Another thing to note is the fact that one of the ways to kill vampires is holy water.
Perhaps related to the fact that Angel's redemption storyline and his struggles with vampirism are a recovering alcoholic allegory (noted by Joss in the City of... commentary regarding the show opening in a bar with Angel pretending to be drunk--note that Liam was a drunkard)?
The Jossverse is always very strong when it comes to thematic imagery such as this.
This is a fanvid that is completely centered on all of the water imagery: https://www.youtube.com/watch?v=KrjbesRqM-g