#Isetta might be the perfect #retrocomputing project, at least in terms of architecture and capabilities. It can run #6502 and #Z80 code, has a graphical OS, and can run games with reasonable resolution & number of colors.
The biggest barrier to growing a larger community around it seems to be that all the components are surface mount, which scares a lot of people. One must also source all the parts other than the board, and a separate board is required for programming the flash chips. An assembled version would make it a lot more accessible.
Surface mount is definitely the way to go. It's really not that hard, and it dramatically increases options for parts and allows for a much smaller board.
Something like Isetta in a case with a keyboard, LCD screen, and battery would be awesome. LCD interfaces aren't much different from VGA.

Isetta TTL computer
This computer is built from simple TTL circuits. There is no microprocessor, microcontroller or FPGA. It can execute 6502 instructions and can on-the-fly switch to Z80 instructions and back. The video has max. 640 x 400 pixel graphics with several colors. It also has on-board file system and sound generator. The prototype is working and runs ZX Spectrum games, 6502 BASIC, and the SymbOS operating system.












