For Super Mario Bros. 2, getting the full experience may be too much to ask, but getting Luigi, Princess, and Toad would be awesome and more than enough! Add on a few of the Mario Bros. 2 bosses, like Birdo, and you’re golden!
I so want the world map editor, so we can create whole worlds for each other to explore, with multiple exits to find! Even if it looks like a simple grid similar to Mario Bros. 3, it would be amazing! Nothing better than making multiple levels to be explored as part of a larger story!
This article was one of the most thought-out I’ve read on Mario Maker for Switch. I hope they add everything you suggested!