I agree Spawnstarion's ending being played for laughs is another jarring shift, especially since he has good relations with several party members by the end.
Watching both his character and mine develop was so spectacular for my first run, when he eventually told my Tav he truly saw her as equals going into the future post Cazador Spawnstarion it meant so much.
I think both spawnstarion and Ascended Astarion fans need to be more accepting of the other side, at the end of the day he is a fictional character and it is ok to like what you like.