I like more artistic portraits too but I have not once, ever, liked the preset portraits these games made available to the player. I feel like they limit rp considerably. In BG1, however, I remember they had an option to upload your own which was GREAT. I'm an artist so I was able to make my own portraits and I loved it. (I've actually painted portraits of people's D&D characters here and there over the years as a side hustle.) But in DOS I remember hating the portrait options and there was no option to easily upload my own.
I think having pictures of the models is good for the base game so people's portraits can look like their character by default. I think it's a reasonable trade-off
But I think we'll also get mods that replace the portraits with more artistic options. I know that once modding is supported, if I can figure out how to do it I'd make a mod that did that.