Your headcanons

Thats also why none of the usual Mario enemies were there. They were on R&R.

It's also why in my headcanon he wasn't very upset he was defeated. It was more a test for his son which he passed with flying colours.
 
Magikrazy said:
Bob-ombs were there, as were Boos, Bullet Bills, and Monty Moles.
They were working overtime.
 
Magikrazy said:
Bob-ombs were there, as were Boos, Bullet Bills, and Monty Moles.

Local to that area hence the bizarre appearance.
 
New Super Mario Bros. Wii is the grown-up version of Yoshi's Island.

It has these:
-Mario and Luigi helpless in a bubble
-Yoshis you can ride on
-Kamek applying magic before a fight
-Luigi getting kidnapped
 
Just not on yoshi's island.
 
Before the events of yoshi's island, a wind waker-esque prologue happened which cause all of dinosaur land to become flooded except for yoshis island
 
Wario and Waluigi were cursed into their troll forms when they were babies due to their bratty behavior. Wario bit Kamek's finger or one of his Toadies(?) and Waluigi laughed at the magikoopa, the turtle witch got angry and zapped them into trolls so their looks can fit with their personalities. Wario and Waluigi felled down by accident and Waluigi felled in a tree and that's why you only met Baby Wario in Yoshi Island Ds.
 
Okay this one may need a bit of prior explanation.

At the end of Yoshi's Safari, the narrator refers to the place Peach is in charge of as the Mushroom World instead of the Mushroom Kingdom. Also when you-know-who said the Mushroom Kingdom was on Earth someone retorted with this:
Anyway, Boo's Mansion, after you get the Super Boots or whatever, there's a quote about secret panels being all over "Mushroom World".
They know the first Paper Mario better than I do but I do know that that game takes place entirely in the Mushroom Kingdom.

So anyway what I'm getting at is that the Mushroom World in SMB3 was also the Mushroom Kingdom which is why in almost every RPG Bowser's Castle and the area surrounding is treated like a part of the Kingdom, because Dark Land is a part of the Mushroom World. Some of you may have objections to this but this isn't the part I consider to be a headcanon I'm getting to that part.

Anyway my headcanon is that Dark Land is the part of the Mushroom Kingdom where Peach for some reason wasn't able to lift the curse placed on the kingdom in SMB1's backstory.

but why would each section of the mushroom kingdom have its own king
I admit that's problematic and I haven't really thought of a good answer. Maybe it was the result of a political kerfuffle resulting from Bowser claiming the part that was still cursed and people being like "well then what's still the mushroom kingdom and what isn't". Maybe we can just ignore every instance of them being referred to as kings and just say they're dukes or mayors or whatever.
 
Those little fortress things that appear after goal flags have toads in them Mario saves.
 
Regarding the Sunshine thing, am I the only one who didn't mind Bowser's voice in that game? Granted I really don't remember what it sounded like, but I don't remember disliking it either.