Very perceptive, I never thought about it that way. I honestly don't think you're overthinking this, Oda seems to have put so much thought into Katakuri's character motivation. So it wouldn't surprise me at all if this was intentional.
My own headcanon is that he's an Oda self-insert LOL. He's trying to bear the pressure of being the franchise mangaka while battling physical and time constraints. Flampe represents the industry pressure from nagging fans and management to create the manga in a certain "perfect" way for their tastes. But on the inside he just wants to draw an imperfect fun pirate comic and HAVE FUN EATING HIS DOUGHNUTS DAMMIT LOL!! To hell with creating "the perfect manga" just be you and the success will continue. Or at least that's how I view the parallel between Kata and Oda himself.
