I think I've made very legit counter points that take into account the series very nature...what you call its "cartoonish" tone or whatever. It seems to me you are doing everything to reject this notion instead of embracing or accepting it.
Why in the world would you think we're somehow required to come to an agreement on this? We're not arguing a question of fact, we're discussing our different subjective reactions to a work of fiction. You're entitled to your opinion, I'm entitled to mine. Different people will inevitably have different tastes and preferences, and mature people respect that fact. I don't like Chinese food, but I'd never try to pick an argument with someone who does like it, because that would be silly; it's not a question of objective truth but of individual reactions. I don't engage in this argument you want to have because there's no reason to argue about it, no "right" answer to be found. De gustibus non est disputandem.
I get you don't like this aspect of the series, but it is there. "Castle" is very satirical. You can't ignore that when doing an approach of analysis like the one you're doing. You are going about it with seriousness in mind when "Castle" and particularly the main character is anything but that. He's serious about his work and career yes, but he also likes to have fun and joke around. Why wouldn't he apply this aspect to his own work?
You're completely misunderstanding my position. I have no problem with Castle's sense of humor. I have a problem with the writers portraying the world unrealistically -- like having the "superhero" killer earlier this season effortlessly bisect someone from head to toe with a single sword blow, something that is physically impossible and that was depicted in a ludicrously cartoony way. It's that carelessness about the plausibility of the world that's what I'm referring to when I call it cartoony. Enjoyment of fiction depends on the willing suspension of disbelief, and these days the writers often fail to earn that willingness from me, largely because the show just doesn't live up to the bar set by the first two seasons.
Maybe we're both just too passionate about the opposite side of our opinions to come to common ground about this particular subject? LOL.
I'm not passionate about it either way; I'm just disappointed that the writing in the past two seasons hasn't been as smart and convincing as it was in the first two seasons. And again, there's no reason why we should have to come to common ground, since it's entirely a question of personal, subjective preference.