You're probably talking about me
...Same with the introduction of Goodman Gray, I think it was an ok character, but the super assassin thing was already being played by Kincaid. Like, imo, Gray wasn't that much cooler that he merited his own story before we got Kincaid's. Or more from Sanya for example. We got three stories from Molly's POV, and I'm glad, because we see the development of this character and I wish we could see more from those people that are already in the story...
Yeah.. I liked Goodman Gray, I liked his participation in Skin Game, I didn't care for him in Peace Talks, and honestly the whole thing there with Justine was meh, but anyway. I suppose that after the assisted suicide situation and Ivy's reaction to it, it's not like Kincaid could just show up for the SG heist, because it wasn't the story for that reunion. I'm guessing Murphy's death will add to some things now in how Dresden and Kincaid interact with each other. I'm guessing that Kincaid coming back to the story would maybe have some kind of importance overall. So, obviously he couldn't be in SG or after because it wasn't time yet and another character was needed, so we got Gray.
And he's not bad, I just didn't find him interesting enough that I would want to read a whole series about him. The only thing that's worthy of attention is the 1 dollar fee thing, but that's not compelling enough for me yet. I feel like we already had some very interesting characters from which we could have more backstory or sidestories, Kincaid is one of them. Another one is Sanya, even Eb or Billy, people in the Paranet. They are already there, I don't think we need to get all new characters all the time.
I guess it could be argued that maybe Jim already has plans for them and maybe other character's POVs might reveal too much at the moment. But the Molly stories worked out just fine. I wish we had more stories like Molly's, we got like how many already, three, four? And they've been interesting and they added information to the central plot. I'd like to see more of that with the characters I've mentioned or others we already have.
Personally, I'm not really that interested in spin off stories, I want them to add to the main plot eventually. The only character, at the moment, I might make an exception for is Sanya, like maybe a short series of three novellas, about him before being a knight, becoming one, and his first years as one.