Bring back the cast of SF characters

When the books about the Ponzi scheme perpetrated by financier Bernard Madoff are written, one of them
will probably have a “Cast of Characters” printed somewhere between the front cover and the first chapter. Essentially, a cast of characters is a handy
“cheat sheet” that helps the reader keep the characters straight. This feature appears in quite a few books about business history, including Den of Thieves (1991), by financial journalist James B. Stewart, and, more recently, King of the Club: Richard Grasso and the Survival of the New York Stock Exchange (2007), by Charlie Gasparino of CNBC.

There was a time when science fiction books included a cast of characters, although here it seems to have been primarily for marketing purposes. For example, of the more than 100 Martian science fiction paperback books in my collection, a few have a cast of characters. Interestingly, all of them were published by Ace Books from the mid 1950s to the mid 1960s:

• First on Mars (1956), by Rex Gordon

• The Mars Monopoly (1956, double novel), by Jerry Sohl

• The Martian Missile (1959, double novel), by David Grinnell

• The Secret of Sinharat (1964, double novel), by Leigh Brackett

• The Martian Sphinx (1965), by Keith Woodcott

I don’t know if the practice of including a cast of characters in SF books has ended up on the dust heap of history, as I read only an armful of science fiction novels each year. If so, perhaps Ace Books, or another publishing company, could bring back the cast of SF characters.