NunuXD
Imagine Gabe making monster hunter and the player have to fight fatalis 💀. Or if he made terraria and they have to fight the moonlord 💀.
I say make skyrim, MHW (It has the best story and mechanics Rise was doing too much but maybe change the handler where you could choose between Rise hadnler, the serious hndler, your handler, or another from the old games), and/or Warframe. These all have varous weapons and can train you in all forms. Warframe is probably the best when it comes to microtransactions to earn money as everything you can buy with money you can grind for it. Dark Souls, Dragon Dogma and Elden ring would also be good games to consider
Skyrim or Obliviin of the elder scroll series might be a good option as they both have multiple weapon choices and dragons shouts, transformations and magic that could work for the developer to get as powers. Plus quite a good story. You could somehow connect minecraft to it and show how the developer makes it more about the survival element.