Amazing sculpting and I am even more amazed that someone like Foundry has not snapped you up.
I have been following the thread hoping to see how you sculpt “crests” but seeing the way you made the shield I think I have worked it out 👍
For the crests im using a base of plasticard or metal foil cut to the aproximate shape. I lay some putty on the one side, sculpt the details, let it dry. Then the other side. Its not difficult, at least for the standard crests, its just tedious with alot of waiting time in between.