I feel like Charmander's eyes should be a little bit more forward facing and the design of the body seems kinda off, like it's lacking the smaller upper body of its traditional artwork.
Squirtle looks fine for the most part, I like that the shell design is really good in it and Torterra's models. Squirtle's face though has something wrong with it, I think it's the mouth, I probably would've preferred if it was more beak-like since at the moment it's got this weird human-like smile to it. Also its wrists could use improving since it looks like the hands aren't properly connected to the rest of the arm.
Bulbasaur and Pikachu both look fine, I think they should've made Pikachu's cheeks more chaotic in their colouration, since in reality you're looking at something like Spinda's fur patterns with those and the black tips on the ears. Otherwise the design is overall fairly solid. I feel that Bulbasaur's design is really quite balanced, and it's a toss up between it and Pikachu's imo for which is better.
