If it isn't broken, do you fix it?

Let's say you find a really simple core loop in gameplay. Let's say, that core loop of a game goes as follows:

player goes somewhere -> enemies spawn -> player lays the smack down on the enemies until all the enemies are gone -> go back to beginning of said loop.

Keep the controls simple, the enemies plentiful and the levels busy with all kinds of interactive objects going off. Get rid of some of the archaic junk like lives and save points in favor of systems friendlier to the player that lets them keep their progress. But sheesh, getting dumped on for lack of innovation when it seems like they just want to see innovation for the sake of innovation?