The ones who actually make the team better dont consider themselves to be rockstars. There is a correlation between humility and talent (otherwise known as the Dunning-Kruger effect).
... This is how they like to imagine they are, but not what they're like in reality. In reality they are childish and petulant. If their authority and awesomeness is not recognised they will make everyone else's life hell until it is.
Like I said, I don't think you've worked with them before. What you describe is most definitely not what people consider a "rock star developer". And, they don't go around calling themselves that, either. Other people do.
The two I've had a pleasure to work with were both very humble, and incredibly good at what they did. Everybody who worked with them got better for it... I know I did.
Largest organisation I worked for in that capacity was 80 staff with 20 developers (most in a consulting capacity). In fact that's why I ended up managing the dev teams, we didn't have enough of them to justify their own manager so it fell under my jurisdiction as IT manager.... I had a pair of senior devs who could keep the team together and moving and were great at it, I considered it my job to keep things out of their way so they could do their jobs.
Ok, not a big company, but still very bottom-heavy. One senior dev per 10 developers, and one manager for a group of 20... it explains why you do have values of a manager in a big company -- since your team works like one.
If you had 4 senior devs that could "bang out" high quality code, each could do that and still lead 2 more junior developers, and your team would be almost half the size and finish in the same amount of time. And, with that smaller team, you might actually be able to dedicate some real time to individuals you manage.