Questions I'm still pondering:
What was that device Spock was holding in front of his face that enabled him to see the orbs in the well? Why couldn't he see them without the device? The answer to this second question is likely that they were in a different dimension or whatever - but if that is the case, why could that device allow him to see the orbs but not his crewmates?
Why, when Spock looked at the orb that floated up, did he see the same little monster screeching at him that he saw when he mind-melded with Batel? In the latter instance, was he seeing Batel's Gorn DNA's embedded genetic memory of the Vezda, or are the Vezda in the orbs perhaps proto-Gorn? Are the Vezda and the Gorn related somehow? Could the Gorn be, say, genetically engineered versions of the Vezda designed to hunt and exterminate them? Or were the Gorn originally designed as host bodies for the Vezda "spirits"?
I like the mysteries this episode introduced! I wonder if we will find out more about the origins of the Gorn, the Vezda, and maybe even the Q by the time SNW ends. (I understand we're getting 1.5 more seasons after this one.)
Whatever the Vezda are, they're so ancient that not even Pelia knew about them. (The fact that the technology powering the Vezda's prison hasn't broken down after millions of years is remarkable!)