>>36403150Absol being dark wasn't really a mistake, they should have just dual-typed it to Fairy or something, at least for the Evo.
>>36403166It's not that it'd be overpowered as much as it would be that it would break the pacing of Gen 1. In Gen 1, you weren't even supposed to know that Dragons existed until you got to Lance unless you caught a Pokemon never mentioned in the Safari Zone or grinded out the Game Corner.
Ice Pokemon are also meant to be trap cards against Dragons, and as badly designed and unnecessary as that is, it also fits the Gen 1 pacing: you don't see Dragons until endgame, and you don't see Ice Types until very late in the game and don't know the significance of using them against Dragons until later. In fact they probably gave the player Lapras at Silph Co. just so you'd have a fighting chance against Lance if you never really looked for Ice types at Seafoam Islands.
Now Fire/Dragon Charizard throws a wrench in that, because you'd get Dragon typing before even going to Silph depending on how much you abuse your Starter, and you'd have a Dragon that isn't weak to Ice at all, only weak to Rock Slide and EQ. It would break the already shaky balance of Gen 1 over its knee.