Even the character mission music suits some of the characters perfectly:
Samara is an Asari Justicar, a warrior monk of sorts. Just listen to the music and try to tell me you don't think about ancient warriors
Mordin is a scientist, so they gave the music for his mission a "techie" vibe. They did the same with Legion's music too.
While not a squadmate, David is a minor character from the series. This music plays during a scene in Overlord. I won't tell you what happens as it's spoiler territory but it's pretty damn tragic. Depending on your choices, you hear the soundtrack again in the third game.
A lot of 3's music has a tragic vibe to it:
But these ones are quite hopeful
And I can't really talk about the music produced by this beautiful trilogy without mentioning the romance themes:
In my opinion 2 had the best romance theme.
Of course, there's this music too:
I could post post after post about the amazing soundtrack, but I'll stop here
