The Difference Between Proper and Non-Proper Rips

"But you can say things like- for MP3 encoding, only use LAME 3.98, only encode at this VBR setting or above, etc."

I thought LAME 3.98 was still beta, and that LAME 3.97 was still the recommended format. Also, not all games have the same level of complexity going on in the background music. A required -V bitrate may not be necessary since it would only increase size without any quality benefits in certain games, such as in GoldenEye 007 (N64) where most tracks don't need anything about ~128kbps (-V 5) (some tracks go as low as 80kbps such as Streets and Depot).

You could also apply the same concept to mainstream music. For example, from Metallica's ReLoad, Fuel doesn't need nearly as high a bitrate as The Unforgiven II, even though Fuel is a more "lively" track than the latter.

Jam it back in, in the dark.