Removing the "Metroid Prime" from the title would ultimately defeat the purpose of the game being a spinoff title intending to expand the Metroid universe in a way not as easily done in a mainline Metroid title, such as delving into the role of the Galactic Federation's armed forces and their place in the conflict against the Space Pirates. While not totally impossible I suppose, reactions to Metroid Other M and to a far lesser extent Prime 3 show that incorporating such material into a mainline Metroid game often come into conflict with what fans view as core staples of the mainline games, such as the sense of isolation. While Prime 2 covered that grounds to an extent through personal accounts gained from scanning deceased federation troops, that method of lore building can really only be taken so far in this case.