OK, I searched, I don't think anyone has done this before.
The recent topic about finding a home version of Ms. Pac-Man with the speed up hack got me thinking. Are there other hacks people prefer to the "real thing." (Heh, really Ms. Pac-Man is a hack of Pac-Man itself, if you get into the history.)
I'm thinking of stuff like the Pac-Man/Ms. Pac-Man speed up, Tempest Tubes, Galaga with the turbo shot hack, etc., etc. Myself, I'm growing quite fond of the Super Missile Attack hack for Missile Command. It's a little bit harder and a little more random. Just enough make a game I've played a million times suprize me.
It's too bad that so many retro packs miss out on these things, though, IIRC, you could go Tempest Tubes on the Dreamcast Atari pack. A lot of these things were pretty common back in the day and many people still remember the games this way.