Also note that due to manufacturing limitations (courtyards in PCB design), you usually only get one "very good" place for the bypass caps, and then the place for the next parallel one is considerably worse. A capacitor is much "larger" on board than it physically is.
Now, energy density of modern capacitors isn't problem; board assembly is likely a limiting factor. For example, you may decide to limit yourself to 0402 parts because you want to prototype it by hand, or use less expensive fabs. Now for say 3V3 rail, 0402 is already big enough that you can get any capacitance up to about 0.5 to 1 uF actual. The point is, you won't get any stray inductance benefits from the 1nF or 10nF parts. They are all the same, if you use the same package.
So now if you place your 10nF capacitor at the best place, all you are doing is add extra stray inductance by having to place 100nF further away. And because they both are 0402, they both add some 2nH. And that 100nF capacitor is equivalent to a stack of ten 10nF capacitors in same but thinner package, placed on top of each other. It's manufactured from multiple layers of electrodes, after all, and for your impedance plot, what matters is the distance to the closest layer.
So now the combination of 10nF and 100nF is only performing worse than if you just put the 100nF at the closest footprint. Or, if you placed two 100nF capacitors in the same footprints, instead of 10nF and 100nF. You would then be paralleling mounting inductances (to some extent; one of them is further away from the device pin, though). Additionally the risk of creating resonances is lower, and you have limited BOM lines and cost.
Ignore the advice of using many different sizes unless you know what you are doing. Similarly, ignore advice of creating split ground planes. These are tricks that are rarely useful and require careful understanding because they are full of complex traps.
Use one part# of ceramic cap on each DC bus. Adding a high-ESR bulk, though, is often a good idea, and given enough ESR, it can't do much harm, and can potentially do good for damping. This is less risky even if you don't analyze it well.