I feel a little awkward. The last thing I would want is for my comments to be taken as demands or nagging. They are just comments. Not a guide to action or anything like that.
In general, for the (mostly named) character portraits to match the in-game descriptions, then I would probably emphasize four things:
1. Hair color.
2. Eye color.
3. Skin color.
4. Clothing color.
As you can see, it is more about colors. I don't remember doing in text descriptions something like "he has a hunchbacked nose" or "she has a dimple on her chin". Also, the cut of clothing, etc. is not much of a concern. Well, I don't remember describing knots or patterns on clothes at all. Which means there's quite a lot of leeway for interpretation.
I often mention colors though, meaning if a character is wearing a white dress, there might be a mention of that. And if in an alternate portrait, I don't know, the dress would be red, the player might not realize what white dress is mentioned there in the descriptions.
So the faces themselves aren't that important and can be taken as personal preference. And whether Jardissa is young or old is nothing more than a matter of personal preference. She will be whatever the mod author wants her to be. And even if there will be some discrepancies with the text descriptions, I think that the player who installed any of the portrait mods will understand what's going on. So is it a big problem or is it a problem at all? I don't think so.