However, the temptation is real for me to want to build my own level editor to build my game, something similar to Mario Maker's editor. There are 2 main reasons why I probably won't do this.

The first reason is that the "last" 2D mobile game I'm making will be about 30 short levels in total. That's not enough levels to justify building a level editor for.

The second reason is that I will be making my games 3D games in Unreal after I finish this game.

Finally, if I make the level editor, I would be tempted to make a character creator, and then an animation editor, and then it will get out of hand and become a flat game design engine when all I wanted to do was make a few mobile games. So, while I feel the urge to build something, I'm going to resist it for now. Maybe, one day, I'll return to that idea. But for now, I see my future in game development as involving something else.