Should I even mention the whole "whisper of the soul"? Should I mention that the Zilartian survivors controls jeuno from the shadows through Armathrawn society? Should the whole meltdown thousands of year ago that split the protocrystal into 5 and created the 5 races of altana be mentioned?
No. No. Yes, but as written in the legend on the Pol page(ancients tried to reach the gods, blah blah, got punished).
You can expand further in a spoiler page, something like [[Zilart/Spoiler]]. I would still keep out major plot details out of this(like what happens at the end of RotZ).
As for the front page, you can also include stuff like structures of those people, and uh so on. Way too tired to get into detail right this moment. There is more nonspoilerous information on those two races than one would originally think.