What TFF needs to be better is not stuff being added, but stuff being removed. Cut out the impossibly high turboshaft. Cut out the nonsensical "center of the galaxy" references -- go straight from Sybok mentioning the Great Barrier to Kirk saying no ship has ever entered the Barrier. Cut out Scotty knocking himself out and that uncomfortable flirtation with Uhura. Maybe cut out or modify the insanely stupid moment where a photon torpedo -- which is supposed to be an antimatter warhead far more powerful than any nuclear bomb -- goes off not 20 yards behind the heroes and they're just knocked down rather than instantly vaporized. (Maybe cut out Sulu's "Torpedo armed" line and redo the FX so it's a phaser beam instead.)
Except for the "Scotty knocking himself out" bit, all those changes would perhaps enhance the experience for Trekkers because they are annoyed with inconsistencies, but wouldn't change anything for the "general audience" who don't know how many decks the ship has, how fast the ship can travel or how a photon torpedo works.