Technical Electrical - Using a master relay instead of multiple smaller ones?

That's a really profound statement, for this thread. Thanks.

As to circuit breakers...they can be useful for inductive loads, though, eh? Like wiper motors, power windows, etc.

 

Since all your circuits should be fused, and fuse blocks are normally inside the cabin, I don't see how you save anything by having relays involved for most devices? You're still going to have load carrying wiring going from inside to the engine bay or tail of the car, but just using a relay to keep the load off the ignition switch or fan stat, etc.
Since some loads don't come on with the ignition switch anyway, why add one big relay, or even more smaller relays? Things like the fuel pump and radiator fan need a relay to keep the load off the switches, but not much else needs one, and it wont save heavier wiring from the fuse block to the relay by adding them. Just makes things far more complicated, and more devices and connections to possibly fail.