I decided to test out editing the Reforged Captain to see what could be done and so decided to create a Silverhand Captain.
His shield and tabard come from the Magroth the Defender model with alterations made to the tabard to fit better. I also fixed some of the clipping issues on the original model as best I could but due to some of the animations I think its impossible to solve all of them. I replaced the Captain's pauldrons with those of the Knight and then mirrored it.
The helmet has been edited for the wings to be more curved and angled to be facing straight back. In attempting to fix the tabard I also found it to be impossible to merge the tabard into the chest of the model so that no gaps appeared in certain animations however the gaps should only appear on the right side which is obscured by his arm and shields in all animations.
After finishing the model I thought I'd create two alternate versions: An Argent Crusade and Scarlet Crusade Captain with their own separate models and skins, however the skins could be used on their own by changing the texture path. To use the separate models just remove War3mapImported\ from the filepath.