A switched fuse panel section has a power buss bar that is powered by the ignition switch. One side of each fuse is attached to that power bar. The other side of the fuse goes to the component. So each component is then fused. The fuses are sized per the component draw. The headlight switch has a fuse/breaker. I don't see an ignition switch burning up. Haven't had one burn up or even get hot in 70 years.
The universal prewired fuse panel type harness kit I always recommend and use does not have a relay. DIY harness is too much trouble and causes overthinking.
If a big draw non original component is used, use a system of direct feed with an applicable mix of it's own big fuse, fusible link, switch, relay.
