As I understand it, there’s a lot more to this story to be told. But the last line of the last episode that I saw sounded an awful lot like “the end”.
Particularly given the subject matter of the show, I’m not opposed to just switching to the light novel, but what do you think?
The last episode sent mixed signals, I think. It both said that the story was over, and also (possibly as a last minute addition) opened the possibility of a follow-on season.
There’s also a particular scene in the last episode that makes no sense for them to have included unless they plan to continue the series.
That said, it may be a while, and I strongly recommend the light novels. They’re highly complementary to the anime and much deeper in their content. Starting at the beginning is best, but if not, start at the end of season 2. The scene where Ferdinand reads her memories in particular is so much more detailed, and season 3 skimmed across some important elements. The novels (and their translations) are quite well written and well worth your time.