Please, we only mentioned four shards, barely hinted at Silverlight, completely ignored the IRE, didn't even mention that Hemalurgy can steal powers from other worlds. Didn't mention how Connection can impact the ability to use Investiture, barely explained Avatars, only briefly saw the Cognitive Realm.
We didn't even get into how medallion technology is basically synthesizing souls, we didn't get to see off world weapons, Adonalsium isn't even mention.
There's nothing on the theorized Dawnshard on Scadrial, or even the fact that Investiture resists Investiture.
I can keep going.