If we had a positive point charge of incredible quantity, does there exist an imaginary sphere about it, such that regardless of the initial speed and direction of any electron, that electron could not escape spiraling into the positive point charge?
Conversely, regardless of the initial speed and direction of a proton (even if it's position starts from within the imaginary shell), it's path could never intersect with the position of the point charge?
No, because the kinetic energy of an electron can be increased without limit by accelerating it close to the speed of light. It will always be possible to increase the kinetic energy of the electron to the point where it matches the potential energy due to the positive charge, so the electron can always escape to infinity.
Similarly you can accelerate an incoming proton to arbitrary energy, so you could get it to within any specified distance of the central positive charge.
By contrast you cannot get the electron out from inside an event horizon because the electron's energy will contribute to the stress-energy tensor and hence the curvature.
