Comet can counter Paks with grenades and smoke/WP while the Stug has a hard time penetrating the frontal armor of the Comet.
My memory is fine and Comet is not an "AI" tank but a tank that has AI which is quite different. AI vehicles are units with primarily AI weapons like the hezter, centaur and Ostwind...
Grenades have 60 range? Notice how I typed Faust support, any pro player like Nicko or Jove will have a gren nearby to snare you the moment you get close. So yes I think a Pak can counter comet. The same way 57mm can counter a P4 or panther with commander upgrade. Just because there's some ability counterplay for the tank there it doesn't invalidate AT guns as a counter.
WP is an expensive vet ability that bugs out and doesn't fire or gets caught on terrain half the time. But you pretend it's brumbar bunker buster barrage by the way you bring it up.
So let me ask you straight up, do you think comet is undeserving of a buff?