I find that Shadowheart lacks that shallow charisma (i.e., good looks) that I found appealing in Morrigan.
Weird, because I think Shadowheart looks a lot better. She also has a lot more character to her while I found Morrigan to be a far shallower sass machine. Morrigan always appeared as though she wore makeup and skimpier clothing, not sure if maybe that's what you found more attractive?
Perhaps.
I wish I could change Shadowheart's hair selection. Not sure why it bothers me so much. I imagine the modding community will come up with something.
She gets a new hair style after a big story moment
You don't know, if it is Shadowheart, who changes hairstyles after a big story moment. I'm pretty sure, all the companions have their big story moments and eitehr one of them could change their hair.
"We are all stories in the end. Just make it a good one."