I think for God-Gale they purposefully broke up the romance path to show that he got the opposite of what he wanted. He just disappeared for half a year, the world moved on without him and hardly anyone cares a smidge for what he has to offer. His whole arc is, that he wants to prove himself worthy and thinks that his only means to do so are his mental skills and his magical prowess, while in reality his worth lies in him as a person. So his Origin-God ending has fun spells but also a touch of loneliness to it and I think it's great this way. Though I suppose Minthara might still take the offer even after having been forgotten for half a year.
In regards to Astarion, I would really like to ask my LI for a daily blood donation - and be lectured about what a bad idea this is, should the LI in question have poisonous blood. ^^ But most of all I would like an option to get them involved in the ritual-scars and start this arc earlier, since the way the scars are currently introduced is very awkwardly paced.
