Is my house's wiring normal?

I have a typical mid-50s CA tract house, 1162-SqFT, 3-bed/2-bath. Been here 25 years and I just mapped the electric circuits and some of it seemed odd to me. The breaker box has four 15a breakers and four 20a breakers; I hope and assume that the circuits all have the appropriate wiring for their current, though I know the previous owner added some wiring.

Here's what seems odd.

The 15a circuits control:
1) nothing
2) one bathroom fan
3) one bathroom fan (and the attic lights the owner added)
4) all three bedroom lights, all three outdoor porch lights, two hall lights, both bathroom lights, the dining room light, and an outlet in the living room.

The 20a circuits control:
1) the kitchen outlets other than the dishwasher and range, one living room outlet, one dining room outlet
2) Six bedroom outlets (2 per room), both bath room outlets, two living room outlets, one dining room outlet, and one garage outlet
3) the dishwasher and range (which is gas)
4) the remaining four garage outlets (including gas clothes dryer); the owner added one outlet here that serves the garage door opener and shop lights, and I suspect one other outlet was added by him.

It just seems odd that three circuits would have nothing and two bathroom fans, while some other circuits are pretty loaded up. I guess my question is whether this seems normal or typical? TIA

That's fairly typical for that era in CA, however until the dead front panel is removed you won't know if the breakers are controlling circuits, or are simply in place to fill a hole, instead of a blanking insert.