Circuit Breaker vs Maxi Fuse

I don't ever, as in NEVER, fuse the line going to the starter. No circuit breakers or fuses.

If you want to protect the car, put a maxi fuse in the line to your starter relay from battery. That's IF the black wire is removed from the alternator and rerouted to starter relay feeding it, like the MAD approach.

I don't know how you plan to wire the car, using the schematic RRR posted is a solid approach using a master cutoff.