We will go back to the neutral route and add content specifically to it, yes, but only waaaaaay down the road. We honestly haven't decided what to do with it. We have some solid ideas: just as example I do have a good idea for a poignant ending that can come out of it, with Asterion and the MC becoming platonic life partners, and we could use it instead to explore some ideas and scenarios that don't fit the main story.
Right now, though, the focus is on finishing the main story. Chances are we will get to the neutral one after that's done, and we will determine how it'll be like based on the state of the game then and how much energy/time we have available.