I feel like a lot of people’s problems with both TFA and TLJ (not all, mind you, both films are far from flawless) - and even the PT to a degree - stemmed from their expectations for how they should be instead of being open to things going down a unique path.
So know that I’m fully aware that I’m setting myself up for major disappointment two years from now when I say this:
Not at least addressing the Knights of Ren in Episode IX would be a massive mistake.