Alright. I'm not much of a lore person but Rise of Iron has gotten me delving into the lore. And I happen to have some theories regarding the story and possibly new exotics in the new DLC
1. The artifacts. When the Iron Lords first ventured to stop SIVA, there were ten guardians: Radegast, Perun, Jolder, Gheleon, Timur, Saladin, Eifrideet, Silimar, Skorri, and Felwinter. However, we only have 8 Artifacts, meaning that Saladin may not be the only one that survived. This of course calls into question what happened to Eifrideet, but I'm going to wait until RoI drops to go into that.
2. (Courtesy of MyNameIsByf) Destiny has admitted that the Iron Lords and their story is based of the Knights of the Round Table, with Radegast being King Arthur. The biggest resemblance is that they both had these magnificent swords. I checked the Bungie database and turns out there's a Titan artifact named Radegast's Blade with flavor text that alludes to a Questline that we will be forging this sword again. DeeJ also said in an interview that we MIGHT be getting new swords.
3. Destiny 2 on Jupiter? Alright. So I have been thinking about this one Grimoire card of Jupiter and it seems very much likely that we will be going there in the near future. Maybe we'll find out what happened to Osiris and Saint 14.
Please comment anything I said wrong here or anything I missed because this is my first lore post and I'm pretty new at it.