Notes from author
A build based on the thematic combo of Executioner Smough and Smaug, the dragon from the Hobbit). Use whatever fire-oriented pyromancies you prefer to fit with the dragon part of the theme. Be aware that I haven't actually tested this build yet, so I have no idea how good/bad/weird the dragon head looks with Smough's set minus the helm.
Since ATN doesn't make pyromancy spells do more damage and only 39 strength is required if you 2H Smough's hammer, move these points around as much as you want to put more points in other stats. VIT is an obvious choice for more HP, especially if you want to sub in the Dusk Crown Ring for more spell uses. Pu tting 58 points into END can get you a mid roll without the Ring of Favor and Protection, but you'll need to take points out of VIT and DEX as well in order to have any spell slots. Lastly, DEX can either be added for faster cast speed or removed to make room for points elsewhere.
As far as rings, if you embrace the fat roll and forego either Havel's or Favor and Protection there are some good choices available to fit the built. The Dusk Crown ring is good for the aforementioned reasons. The Darkmoon and/or White Seance rings will get you more attunement slots if you want more or want to take points out of ATN. Lastly, the Bellowing Dragoncrest ring will make your pyromancies do more damage. Obviously others can be good as well for a variety of applications, but those are the main ones that felt right to use with this build in addition to the ones listed within the build itself.