This is great stuff. I came across this article recently since I've been working on an Amiga game and will soon be evaluating my options for compressing level data. That's one of my favorite things about writing a game for classic hardware—we can take full advantage of modern tools and easy access to decades of documented experience in order to achieve new limits that were not previously possible.
Besides, it's a joy to code in 68k Assembly. Not without its quirks, but it's a very pleasant and readable instruction set.