I am also familiar with the timeline enough to understand any story and when it takes place, but, since they are doing the manga trades, and since I do prefer to read the stories in order, more or less, then it's fine by me if they never do stories of the past anymore. What kind of Sunfolk story could be interesting? What kind of protagonist and antagonist are you going to have? Rayek protected the village for who knows how long. What did he protect them from? Wild animals. The occasional zwoot stampede. No trolls. No humans. No evil elves.
You want to see a particular elf grow up. Ok, but what else is going to happen? Look at the Wolfrider books. You see many familiar elves growing up, but at least there are other events happening to make the story interesting. There are humans and trolls to fight. There is surviving the winter. There's Madcoil. The only story I would be interested in would be the story of how Savah and her early kin came to Sorrow's End. Unless of course, no threats of any kind came their way and they made it unscathed. Or, I would like to see how each surviving High One made it and what came of them, unless of course nothing happend except the basics of survival: hunting, finding shelter, making sure the tribe was safe. You see these basics in the BoTC and Wolfrider books. Read the BotC novels if you want to get a better insight of past chiefs. As for the comics, let's finish the unfinished first.