The entire thing needs beautifying >.< the sprites/paperdolls/weapons/items and colourscheme all look terrible and it makes my eyes sad :c
Edit: and the BGM and sound effects...
Yeah, it's not a very pretty game, and the BGM is a bit too campy for my tastes.
That being said, the BGM on MIDI does sound a lot better. I do like that hard clicking sound effect for the gas cannon reload, and the muffled quality of the sound effects for the weapons does make sense for underwater missions (but considerably less sense for land missions.)