Truly truly meaning no offense or disrespect, but I think you're grasping at strawhats a little bit.
I don't see how losing Chiffon would matter to her crew strength at all; we don't know if she's lost Pudding yet - admittedly if she has, she'll be missing out on a very valuable set of powers; we don't know if she's lost Pekoms yet - and if she did, he's only a mid-level soldier, and would be easily replaceable; Katakuri's defeat and freakiness could very easily be something that the crew spiritually recovers from after the initial shock - I'm not saying it wouldn't effect them, but we can't really say the effect it'll have; and we have no reason as of yet to believe that Big Mom will be permanently incapacitated after the cake. Again, all the respect - you make good posts, and some things you said could happen, but so far it's too much conjecture for me to feel like the Big Mom Pirates are in trouble.
Who made the fluffy cake? Chiffon. We've clearly seen that the family doesn't always keep items on hand for when Mama gets a craving and goes on a rampage. Nowhere in the entire kingdom had the cream puffs that would calm her down til Jimbei showed up and just happened to have some on him, and it would have taken time to make whatever it is she craves, all the while she's tearing stuff up and potentially killing people, even her own children, until she gets what she wants. Being able to make something that specialized in that short of a time, even if it's only for calming Big Mom down, is pretty damn important, although I think at this point they're going to splinter further anyway and she'll have to learn to get over herself or risk losing everyone and not just a few. What good is having a strong Yonkou as a leader if she's indiscriminately attacking both allies and enemies? If you don't have non-combatants who are able to provide other means of support like Chiffon and Pudding, you're not a very well-structured group and that's detrimental when you're supposed to be one of the dominant power bases in the world.
Pekoms is stronger than you're giving him credit for, if not offensively then certainly defensively with his tortoiseshell defense, not to mention Su Long which, I'm sure, would have made him extremely formidable if he hadn't gotten caught before it fully manifested. Poor bastard. Really hope he doesn't have his eyes gouged out like they were saying. Katakuri on the other hand, having his entire fan club losing faith in him, while it didn't exactly demoralize any of them as they were content to simply mock him as he invited them to do, definitely can't be a good thing since it now makes their whole group look weaker as a result, and their confidence at least had to be shaken. Even with him acting the fool, they surely didn't expect him to lose. The main reason I bring him up is he's the best one to say, "Look at all of you! Bunch of damn losers! Look what following Mama on her madness has gotten us! Let's turn this around and not let it happen again, by following a different path!" if indeed Big Mom somehow does shut down after all's said and done. He's one of the rare enemies to make such a turnaround even before officially losing, and that's pretty remarkable. I want to believe he'll become a better character and try to spread that improvement to others as an inspirational leader and he won't have that chance unless the family splinters or Big Mom is incapacitated and he needs to step in as temporary head of the family.
While I had a sense that Kata would do something to even things out with Luffy due to the interference in their fight, I wasn't quite on the mark when I predicted he'd heal Luffy with some mochi skin grafts, but there might be something he arranges to happen to help repair some of the damage to the ship, like using sticky mochi to help temporarily glue the separated bits back together until a more permanent solution can be made. It would be cool if he did it in secret, and thanked Luffy for getting him onto the better path he'll be on.