Quote
Full mouse binding support.
Texture scale filter Scale2x hq3x/hq4x or similar.
Better audio channel positioning.
Full 5.1 surround sound.
Ogg/flac/mp3 soundtrack playback.
Cutscene audio.
fov slider
Dynamic lightning (gunfire/explosions)
Splitscreen co-op.
And reintroduce the Napalm Launcher secondary fire.
Surround sound and Dynamic lightning are more closer and useful to activable hires content than other, for the base game is too much. Also
the scaling does not guarantee the visual improvement, it depends a lot how the sprite is. For practical example some games on Scummvm looks less charming when a filter or the wrong filter is applied, often emphasizing the defects that raw pixels hides.