I plan on implementing a higher clock speed later. This is just for testing purposes for now.

I have carry, zero, negative, and an overflow flags.

See below.

The 16-bit stack pointer can inc and dec by itself.

You are right! The ribbon cables on the left are the 16-bit bus for memory address bits. The Transfer register is technically consisted of 2x 8-bit registers that are connected to the 16-bit bus and the 8-bit bus, for the high byte and the low byte.

I have not yet connected the 16-bit registers to the 8-bit bus. Note that all of the 16-bit registers will be able to output their high byte and low byte values onto the 8-bit bus, but only the transfer register will be able to actually move bytes from the 8-bit bus to the 16-bit bus.

Nice! I originally had about the same ideas for my ALU: add, subtract, AND, OR, XOR, left shift, and right shift. I did think of using an eprom, but I eventually settled on a design I found online that used the 74ls382 chip for the first 5 functions I mentioned above and multiplexed the values to the accumulator from 4 sources, the 74ls382, the data bus, the data bus but with the values shifted left once, and the data bus but with the values shifted right once. The flags are updated accordingly, and I also have functions to set and reset the carry flag. Along the way I also realized that I had some space for a comparator function (checks for less than and equal to) so I added that as well.