So from your pictures you would rather play a game full of nasty old looking witches, and Samus is just another "normal curvy girl" in a robot suit which would probably come out as a skin and then put into your list of big breasted women. As for riot not having creativity for female characters I think they put more creativity into orianna than blitzcrank. If you don't like the boobs buy a skin, If you don't like "normal women" play another character. I think riot did a great job with the characters,
Btw you forgot about Lulu,Leona,Lux,Karma, and Orianna in your list. I don't think they've showed enough cleavage for this to be a problem not that I think it ever will be, since it is a characteristic that defines women.