I've largely ignored revising the plot since last time but i posted something awhile back,
here .
That should safe me plenty of minutes typing. Now for the new ideas.
All i got is this
Wario was just relaxing in his house when he realizes he blew through most of his money on garlic flavored foods after some good sales on his microgames. It then occurs to him that he got lazy by just doing microgames and hasn't been out treasure hunting in a long time. He goes on the internet to look up some legends about treasures and find that across the ocean there is an archipelago. Each island has a temple with a piece of a big valuable gem inside. So he gets the ol' Bull Dog out and flies to the archipelago to get rich.
As for the end, Wario gets all the giant gem shards and an island in the middle of the other islands rises from the depths of the sea. Throughout the game there would be hints of an old civilization on each island. There would even be ghosts of soldiers with spear as enemies (Ghost versions of spear gooms perhaps, haven't planned out all the enemies and what not.). When Wario breaks into the temples it angers the old gods that the people worshiped so the island rises and the gem is somehow (probably magic) taken to the top of that island where the gods have provided some final challenges for Wario to overcome then Wario's gotta fight the big man himself for his gem and then Wario makes off with the gem.
The ending much like previous games is determined by money and treasure that you get throughout the game. You see after Wario won the fight the god bows down and hands him the gem out of respect, Turns out that was a trick. He took the real gem straight to heaven after Wario assembled it and Wario was handed a fake gem worth one coin (1 coin is jokingly added to your net worth before the ending is determined. This means that Wario must rely on what he found on the island.
I have not come up with treasure requirements for the ending other than Rank S needs all treasures and 99,999 coins and Rank F is a secret ending requiring 0 treasure whatsoever
Rank F ending: Wario comes home empty handed and says something like "Wahhh~ How rotten". After brooding for a bit he goes inside and eats a sandwich or something.
Rank E ending: Wario's bag is pretty shallow but he has *something* in there. He adds the money to his stash and throws his arms up in defeat with a face that says "Doh, i'll get it next time"
Rank D ending: Its like the rank E one but the bag isn't totally shallow and Wario is somewhat pleased he has more treasure
Rank C ending: Wario arrives with a larger money bag and laughs to himself as he adds the treasure to his stash. Like all the other endings except the S Rank one there's a try again screen after the credits so despite this ending being pretty good you would at least be inclined to find out how much better it gets
Rank B ending: Wario makes it home but instead of carrying his treasure its in the big bag, its tied to the bottom of the bull dog and is full to bursting. The plane starts to lower in altitude from the weight but at least Wario can drop the treasure in front of his house. When Wario touches ground and see's gold all over the place he seems pretty darn happy.
Rank A ending: Wario buys a bigger plane before going home and in the back of the new bull dog is a a few seats with treasure bags behind them. Upon getting home it takes awhile to unload the treasure but after that it cuts to a shot of Wario with golden statues of himself outside the house (a nod to Wario World). There's also some aesthetic changes to the house making it apparent that he's rich now.
Rank S ending: Wario has so much treasure that he can build a tower with it straight to the heavens and It unlocks a secret final boss. If you go back to the regular final boss you'll get the Rank A ending, after fighting the tougher version of the fight Wario takes the real gem with him. It then cut to a shot similar to the beginning of Wario World where Wario is sitting on his throne surrounded by tons of treasure laughing to himself in victory.