Gale has a few individual lines for the other origins. For example every origin has a line about envisioning harmony during his magic lesson tailored to them (just like they each have a special line in Shadowheart's wine scene) and he has at least for Astarion and Shadowheart-Avatar lines that compare them to Tara. He also has modified epilogue dialogue for romanced Avatar-Astarion, Karlach and iirc Wyll.
Avatar-Karlach has chunks of Astarion's romance modified for her.
