I'm not super concerned about the casual outfit, bioware has a history of putting out new ones (leather jacket, hoodie and dress/suit from ME3 come to mind) so I'm sure they will do something similar. Hair though, is an entirely different beast.
Were those patched in after release additions though? If I recall correctly, the hoodie was a collector's edition item. I remember always having the leather jacket, but then again I didn't get ME3 at launch.
Hoodie was collectors, N7 jacket was in all versions on launch (as was the leather N7 dress), and the dress suit was new (added in during Citadel DLC) for a mission and cutscenes, but isn't accessible as a casual outfit without modding.
The largest problem is that there isn't anything in game that allows you to change outfits yet. They can't just make a model and add it to a menu, they have to make and patch in a whole new system that allows you to preview the current outfit and change between selections in real time, plus add an interactable that allows you to access said menu. It's far more than people realize, way more than adding new hairstyles or tattoos, or adding a Mirror of Transformation, as the menu it links to already exists. I dunno if they'll consider that expense worth it.... I hope they do though, I'd buy it.