Toejam & Earl is definitely an interesting game for the Sega Megadrive. Pretty nice wikipedia article on the game, too. I like that it has connections to Rogue.
I have practically no experience with MSX and the Japanese computers, so that'd be bold new territory for me. My first computers were the Vic-20, Commodore 64, Amiga 1000, 3000, and finally a PC and Mac. I dabbled in DOS and Macs along the way, but sadly missed out on other platforms (been catching up via emulation).
I adored the Turrican series and played them all (with trainers, of course.) The music is wonderful on those. I also liked the Metroid games on the NES/SNES, which have a lot in common with them. I wrote an article comparing the two games way back in 2004:
Thanks for buying the book, pbareges! Let me know what you think.