This has the sound of grooviness to it. One on hand, electrons as point particles sure sounds empty enough. On the other hand, the fields fill everything. Bu

This has the sound of grooviness to it. One on hand, electrons as point particles sure sounds empty enough. On the other hand, the fields fill everything. But on the gripping hand, you could set the volume of the electron to something ludicrously large, like the volume of a proton, then use the charge distribution of whatever "orbital" to trade that charge for an equivalent amount of proton-volume, as sort of a percentage filled of unit volume ... integrate, and you could get a sense of the density. That, I think, is about as fair as you could ask for when dealing with point particles that are still smeared around.