Ask HN: What is good circuit designer and emulator for me?

Hi, I'm planning to build a 8 bit CPU using TTL logic gates. I'm having difficulty finding a circuit designer and emulator. Emulation is critical for me since I need to debug before implementing the circuit to lower the costs because logic gates are really expensive in my accessible markets.

Logisim was promising before but I had hard time using it.

Are there any good circuit emulators for my use case? Thanks.