Lae'zel. In fact, isn't there literally a quote about Lae'zel breaking her chains? From Vlaakith.
Shadowheart. Breaking her chains from Shar.
Wyll. Breaking his chains from Mizora.
Dark Urge. Breaking his chains from Bhaal.
Karlach. Breaking her chains from Zariel.
Gale. Breaking his chains from the orb.
It's a theme throughout the entire cast of characters.
Entirely this! I always interpreted I Want To Live as a song for all the party members, who share the theme of breaking chains either literal or mental and wanting to live in spite of the obstacles before them. Astarion wants to be free and have a chance to finally live, but Wyll wants to be free from Mizora and not be damned to the Hells as the reward for his sense of duty, Shadowheart wants to live and experience more than grief and loss and stifling servitude, Karlach wants to live despite the engine as a ticking clock, Gale wants to live despite Mystra's mandate of suicide, Lae'zel wants to be more than a sacrificial lamb for Vlaakith and can finally experience life beyond that of a child soldier, Durge wants a chance to be themselves more than the Urges... etc.
'Your blood like wine' is pretty Astarion (or Durge), and reading our own interpretations into the songs is a free country - heavens know I've done it with several already. But claiming the song belongs to him and that every other interpretation must be cope/Mary-Sueing is myopic towards all the other characters. BG3 is very thematically tight and the origin characters share a lot with each other. I also don't think 'invite me in' has to strictly be about vampires when the metaphor is just as plain for two people getting to know each other and letting each other past each others' walls - which is, again, something that happens with all the characters.
It seems way likelier to me that a song was created with elements of all the characters in mind (or if it leans more heavily on one specific character vs the open-endedness of Tav, it'd be Durge) than that one origin got special treatment the others didn't.
Though on the topic itself - agreed that The Power and Last Light are both gorgeous, the ending credit version made me cry that first time, but I've gotta push a couple of other favorites from the soundtrack.
The battle music in the Shadow-Cursed Lands. Absolutely legendary buildup.
The music box version of Down By The River
Cazador's battle music. Again, terrifyingly good buildup with that aura of dread and the off-key violins.
