Those were the original JP sprites (Green/OG Red versions.) The US ones look a lot better but still seem off with some of them (like Psyduck, Golbat, or Kabuto.) I don't think they really got the sprites down until Yellow, though by that time they had the TV show inspiration to help too.
I don't see what is wrong with Psyduck in red sprites...? Also Kabuto is pictured from above. But yeah, Golbat
But yes, Yellow had rather decent sprites. Interesting though how Gyarados hasn't changed like at all from Red sprite. There is some other too, but that Gyarados sprite could very well be from Gold/Silver if colored appropriately.