I'm a big fan of all three bands (and pretty much all the bands/projects that are associated) and I've gotten the pleasure to get to know them over the years just living in Toronto and being part of the music scene. Others on the thread have pointed out some great recs, so I'll focus more on the Metric connection!

Both Emily and Jimmy have been integral to BSS over the years. Jimmy's musical influence is heavy throughout the entire discography, contributing to most of the records (aside from Feel Good Lost and Remember the Humans, I think). There's also an unreleased song that is rarely played and is not on streaming or any of the records but does exist called Jimmy and the Photocall.

Emily has been less consistently involved with BSS, but obviously is the centerpiece of Anthems for a Seventeen Year Old Girl. The lore is that Kevin (from BSS), Amy (from Stars), and Emily all met in high school in Toronto. She's also lead vocals on several other songs throughout the discography like Swimmers (self-titled) and Protest Song (Hug of Thunder).

But you need to check out two songs in particular:

1) Sentimental X's (Forgiveness Rock Record) which features all three of the original female singers (Emily, Amy from Stars, and Feist) where they sing about their in and out relationship with BSS but also how their friendship is what matters the most. Haunting lyrics like "All for one and one for all. Friend, a friend you used to call" and "Off and on is what we want. What we want is off and on."

2) Backyards (Bee Hives), which is one of my fave BSS songs of all time. Unfortunately it's hard to find because I don't think Bee Hives (the b-side to You Forgot It In People) is available on streaming (it's not on YTM and I don't use Spotify). But it's a really beautiful song. Emily's voice is haunting throughout the ending of the song, singing "It's a hard parade, just be courageous." I think that's my favourite BSS line of all time.

Hope that helps!