Yeah, the proportions are off on this one (I don't draw as well in a realistic style if you couldn't tell by now). But this is just the sketch, perhaps when I'm about to color it I'll fix it all up.
This isn't from any specific Metroid game, theres a bit from a few of them such as the lizards from prime, the ship from zero mission, and the rain from super... But all in all it's just Metroid.
I plan on making Ridley more menacing... heh, he has too much of my cute style I think. I'm also a little unhappy with how much I packed into this one, I feel like Kraid shouldn't be there, and many other little things as well. The Metroid series should be about isolation, I don't feel like represented it properly. So if and when I ever do color it I'll probably change a lot (not to mention Samus's proportions).
I didn't even notice Kraid was there. (lol) I don't think there's "to many" characters on here personally. The games do have some areas that are pretty full of enemies.