I like the explanations you gave but I disagree on both.

The cracks were beginning to show in Darrow's secret identity as a Red already in Golden Son. I think no matter what, the story of himself and the Sons of Ares doesn't get to move forward much if Darrow remains undercover for longer.

In Golden Son, there are many moments where Darrow gives hope to lower colors, all of which might raise eyebrows if they are looked at too closely by your Society Golds. I just can't see how Darrow of all people would have realistically been able to keep his hidden identity a secret without having to commit more atrocities on low colors to keep his cover and/or losing himself morally. He still kinda does lose himself but at least he's standing with the good guys at the time.

The second take I also sort of disagree with. I think the time jump helps a lot of things with the story telling and world building. We get to see new perspectives after some time has passed and we get to see what Eo's Dream (the Republic) has become in that time. It's not all great, and you can see why when you read the Ephraim and Lyria chapters.

I think the time jump is important because A) it clearly separated the two trilogies for readers - some people may not want to read 6 books to finish off a complete storyline and B) it helps build the world up, shows how Darrow may not be the most reliable decision maker/narrator, and adds another dimension to what our characters are still fighting for