I've had the idea to do this for a while, since I love Maxima but so many of its tracks can be found in higher quality on other releases. Tonight I finally did it in Ableton Live, replacing tracks wherever possible and tediously getting them to crossfade as accurately as possible to the original Maxima. I also added the deep bass from MHTRTC's One Very Important Thought to Maxima's version, yielding a rather nice-sounding result.
I'm pretty pleased with the result, but I'm going to give it a listen or two to make sure I don't need to adjust the track volumes more.
Keep in mind, though, that the tracks that were only on Maxima (Whitewater, Red Moss, the Maxima version of Chinook, etc.) have not been modified in any way.
For Carcan, it seems there's no way I can avoid the added sounds from the A Few Old Tunes version. I was originally going to loop it to avoid that, but there's an extra melody that comes in and plays once towards the end (once Nlogax's beat has faded in), so...deal with it I guess.

By "remaster", I mean I'm replacing poor-quality Maxima tracks with higher-quality versions from other releases whenever there are better copies of the same tracks available, and mixing them to match the original Maxima.
I'm not taking random tracks from other releases. I'm taking tracks that are on both Maxima and other releases, and putting the higher-quality one in there. The track listing is identical to the original Maxima; the only differences I've noticed in any tracks are the added sounds in Carcan and the different panning at the beginning of Everything You Do Is A Balloon.
EQing and a bit of high-end reverb, set differently based on whether it's a Maxima recording or an Old Tunes one, and also based on the song itself, to a certain extent. On some of the Old Tunes tracks I added a bit of chorus.
For M9, I set up some auto-panning to imitate the auto-panning in the original Maxima version that doesn't exist on the Old Tunes one (basically, it pans from left to right and back at a set speed).
For Carcan, I was faced with the tedious task of figuring out the perfect loop points to get a seamless loop of the exact right length, so that it would sync up with Nlogax in the same way as the original, without the cut-up voices from the Old Tunes version coming in.