Quoted By:
Even ignoring the glitches let's talk balance. Psychic types had no balance in gen 1. Ghosts were supposed to be good against physichs (in the original red/blue there was a kid in saffron who says physchic only fear bugs and ghosts but he was removed in yellow when they realized they fucked up the typing match up) plus even if they got that correct the gastly line, the only ghosts in gen 1, where part poison which gets anally ruined by psychic. There's bugs but gen 1 bugs where shit. The only one with a decent bug move (twin-needle) was beedrill but it's part poison so we got the same issue as the gastly line.
Then there's the matter of the special stat. Rather than do the special attack and special defense like we would later get gen 2 and onward we had them lumped together into the special stat. That meant that pokemon with high special attack also had high special defense. Most psychic pokemon ran off the special stat which made them even more broken than they already where, especially when considering that back them all psychic moves where special.
You can't run so until you get the bike you move unbearably slow when you're used to the moving speed of the later games. but even then you can't use the bike indoors.
There's more but this post is alreadt tl:dr so i'll spar you the text wall.
Tl/dr: the first games had shit mechanics even fi you ignore the glitches.
