These are all Firefox forks. If Firefox is done, they’re done.

Incredibly comprehensive mod. It’s actually available directly from GOG and Steam, and it automatically installs on top of the game. You’ll hear people saying you should play vanilla if you’re playing for the first time, but no. Play Revision, just don’t enable Shift/BioMod.

If I had infinite storage, for archival I’d preferably use FLAC at its default level 5 compression. But like you and others, I thought the file sizes were quite big for a sizeable collection. So my personal compromise was AAC at 256kbps encoded with Apple’s QAAC. It’s small in size, vastly superior to MP3, and almost as universally compatible as MP3. There’s a reason why iTunes has stuck with it for so long, it’s an incredible encoder. I would never be able to hear a difference compared to lossless, at least on my equipment. So I went with it.