The Macintosh SE/30 is the best 68k compact mac. With its 9 inch 1-bit display, a 68030 processor running at 15.667 MHz, a 68882 FPU, and up to 128MB of RAM, it packs a lot of power in beautifully designed machine.
This is my Macintosh SE/30 running Civilization. (Picture by Javier Borquez 
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This macintosh has a very active indie hardware community out there. You can get new RAM such as these purpleRAM SIMMs , replacement ROMs to run in 32 bit mode like the ROM-inator II . You can even find new boosters and video cards, like zigzagjoe's Booster 2.0
Thanks to the effort of archivist and enthusiasts, there's also a vast pool of software available in places such as the macintosh garden . It can run up to System 7, which gives you a lot of options. Here's My Favorite Software for the Macintosh SE/30
A close-up of the Macintosh SE/30 (Picture by Javier Borquez )