A new cycle-stepped Z80 emulator

Very detailed, I love these kinds of write-ups.

Have you considered writing a GB emulator in this style?

No, I mostly focused on 8-bit home computers so far, and only ventured into other areas when I had some sort of "relationship" with those machines (like the Bombjack or Pengo arcade machines). I never owned a (classic) Gameboy, so... :)

Makes sense. I only ask because Z80 and GB are similar

TLDR: Whats the difference between this and simh?

I don't know too much about the simh project, but at least the Z80 emulator in "simh/altairz80_cpu.c" appears to use the "traditional" instruction-stepped approach with one switch-case branch per opcode:

https://github.com/simh/simh/blob/3621db4e6a5469ba0570fb422c...