I'm working on a dragonborn patch for the smithing part of the http://www.nexusmods.com/skyrim/mods/10037/? mod since Athyra doesn't seem to be active anymore, but would gladly give it up if someone else makes one first. I've gotten the carved Nordic armor and weapons done, but I haven't touched the others. My thoughts are these:

Carved Nordic requires heavy metal smithing and at least a skill of 50. Wearing three or more pieces gives you 10% frost resistance.
Stalhrim requires arcane smithing and 60 skill. Wearing three or more pieces gives a 15% frost resistance.
Chitin armor requires the leather/iron/steel skill and gives 10% fire resistance.
Bonemold requires the same and will give 15%.

I haven't decided on the skill levels for the bug armor, but I'm thinking 30 & 35 respectively since they're fairly "simple" armors. I'm also thinking of adding a new "branch" to the smithing tree for these two, but I don't know yet. I'll take any suggestions though.

As far as I know, Hearthfires doesn't add any new armor and Dawnguard only adds the vampire and Dawnguard soldiers armor, so I probably won't add either of those in since they can't be crafted. I can also remove the automatic perk granting via a modification after I'm done with the main file; basically you'll choose which mod you want: auto-perks or no auto-perks.

Thoughts or comments? I think I can get this out fairly quickly if there's enough interest, but I've only been able to test the Nordic armor so far, so I would need someone else to test the other sets once I'm done. Thanks.