Dragon or spirit for fire auradin?

Help me out here, im a casual player who loves building characters and playing for fun. Along the way I end up with some decent gear but have no idea how to apply it. My auradin is lvl70, maxed out holy fire, resist fire, and salvation. Dragon has a 14 holy fire aura but when I use it instead of spirit it drops my HF down 2 levels. Am I missing something? A lot of guides I read say dragon is the way to go with this build. It’s sitting at 33 rn with gear