I see what you're saying, but I feel you're still missing what we're saying.
Creating a superhero and creating a superhero universe are one and the same. I'm not talking about publishing multiple titles, just one, but you STILL create a universe.
For example, in fact, Forby's favorite example. Pen-Man.
You want to write about Pen-Man. So you come up with him, and his real identity of Bic Biro. You come up with his job, family, supporting cast, his home-town of Staedtlertropolis, etc. And, as Forby says you need at least 5 villains for every hero, so you create White Out, Pink Pearl, the 12 inch Ruler, French Curve, and The Evil Easel. While working out those villains, their origins blossom into a story of their own giving you teen sidekick # 2, and the bizarro-like imperfect Pen-Man clone, Carbon Copy. Which leads you to an idea for Pen-Man's becoming a reserve member of the League of Office Supplies....
Now, all of these characters will appear in the PEN-MAN comic, but you've still created a Universe to put out that one book. And that's only about 1 year's worth of monthly stories!!
That's a good chunk of hero-verse right there.