I built a simple 16-bit RISC processor with a custom instruction set during my engineering coursework...inside a Xilinx Artix-7 FPGA. It was still a lot of work.
> Given that with a PCB instead of a breadboard you'd get higher density...
I can see the appeal of wanting to do this with individual gates on a PCB instead of using Verilog (you can draw bare gates and let Vivado synthesize that too), but you'd have to be crazy to want to do this with breadboards! I can only imagine the frustration of dealing with signal integrity across the ratsnest of individual wires. Which connection looks good but has a loose spring terminal? Yikes! Soldering on perfboard or old-school wire wrap would seem much more reliable, and PCBs are so cheap now that I'd go in that direction for sure.
> Given that with a PCB instead of a breadboard you'd get higher density...
I can see the appeal of wanting to do this with individual gates on a PCB instead of using Verilog (you can draw bare gates and let Vivado synthesize that too), but you'd have to be crazy to want to do this with breadboards! I can only imagine the frustration of dealing with signal integrity across the ratsnest of individual wires. Which connection looks good but has a loose spring terminal? Yikes! Soldering on perfboard or old-school wire wrap would seem much more reliable, and PCBs are so cheap now that I'd go in that direction for sure.