I finished the Nordic Warhammer after much experimenting with ZBrush and it's Polypaint features. I think I now have the Maya/Zbrush process pipeline working functionally and I understand the aspects fairly well, and I just need practise with them now. I'm not happy with the handle, for a few reasons; I think it needed more geometry around the ends, as these areas stand out as quite blocky. I also think the diffuse texture is a bit messy looking, and I could do with toning down the normal map a bit next time.
After it was all finished in Maya I set it up in Unity like an FPS weapon, to see what it would look like. From doing this I realised I shouldn't spend too much time on the part that the player won't even see. The handle would be mostly out of sight. The detail of the stone, especially the damaged parts looks great in real time lighting though.