There should be a perk that causes Bound weapons to deal Fire Damage. They're wreathed in eldritch purple flames; they should deal Fire Damage! --- Hey there, sweetroll; I just cast Oakflesh... if you know what I mean.
It's been mentioned a few times, but are you dual wielding? If you feel like you're not doing enough damage and want to focus on conjured weapons, dual wielding is the way to go.
If you are already dual wielding, then I'd say your problem is with defense, not offense. I have a character that uses bound swords exclusively and no enchants at all, but has capped armor and magic resist, and doesn't really struggle.