Hmm, I'm sure they'll come back at some point...? :L
Well I reckon that if a pokemon's on there, its evolutions should probably be there too. Like Marowak should be there and if Charmeleon is, Charmander and Charizard should be too :3 So should Yanma, Piloswine, Swinub, Tangela... Those should be added ;D What do you think? (:
Seviper I'd agree with since it looks all ancienty and stuff, but ekans and arbok are probably more recent snakes so maybe not for them :3