For the detailing on the hat & coat, I already had some base shapes hidden away as separate subtools, but because I had changed the overall shape I had to realign them. This was easy enough to do using the Zproject brush (such a lifesaver!) and then just using panel loops & some dynamic subdiv to complete. I also used Zmodeler & creasing to add a bit of subtle edges.
When doing symmetrical patterns like the curly shapes on the coat here, it might seem like a challenge to do because the coat itself isn't symmetrical anymore. However, using the Zproject brush for this really helped me out. Maybe there is an even better way to do this, but for me this method works really well. When using Zproject keep in mind it only works on single sided surfaces (so no thickness), and that it is influenced by the camera angle.I know usually people like using the matchmaker brush but I can never get that one to work how I like it so this one is ideal for me.