So could it be possible that Wario Land was originally just a one off name (to 'parody' Super Mario Land), and later games were originally going to use different types of names?
I'm honestly glad they stuck with the title. If they used unique titles for every platformer after Wario Land, they probably wouldn't have stuck to the same general formula as much in subsequent games and we probably wouldn't have gotten the amount of Wario Land-style games that we did. Probably more "kind of" Wario Land-style games like Master of Disguise or Wario World, which are still fine and all, but I wouldn't want to be left without games like Wario Land 3 or Shake It.
This is just the English version, the Japanese would've probably still called it Wario Land. Maybe some overly long title like "Wariorando okane kasō shōnen to hottona on'nanoko no tame no tankyū ga nai onara konkai"
Throughout its development history, Virtual Boy Wario Land went through at least two or three working titles that were made public. Wario Cruise and Wario's Treasure Hunt were among them, though there was another one that eludes me...