A lot of this discussion pertaining specifically to Misty's difficulty strikes me as theoretical anyway because I can't think of an instance where my 1998 self wouldn't either have had a properly leveled Pikachu on hand or had just dumped all of my EXP into my starter and overpowered every bad match-up.
This is what I was referring to here
Anyway my main point was that one would think she'd be higher up on the list if many more kids had been traumatized by their starter Pikachu being destroyed despite the apparent type advantage—which isn't the case unlike with Whitney's Miltank.
Misty's Starmie in theory has everything to absolutely wreck you if your only option is Pikachu (either the starter or the Viridian version) due to easily tanking Thundershock and doing a ton with BubbleBeam but due to poor AI there weren't thousands of kids with PTSD after the fight. Like sure, Pika can live a hit and paralyze but it normally shouldn't win one on one unless it's overleveled.
So yea she could've been much harder in RBY than what she realistically ended up being.