Dark Samus is the only reasonable candidate. Ridley is also acceptable but would probably be an extremely awkward character given their body shape - moreso than even Charizard.
The rest are all either faceless, one-offs, or stationary objects. Adam could count as either of the latter two. Besides, Alex from Golden Sun (the main antagonist) would be a better ice character than Rundas.
Dark Samus might seem like a clone of Samus at first, but frankly, anyone who has played Metroid Prime 2 or 3 should know better - the only attack they have in common is missiles. Technically the Boost Ball as well, but Samus isn't using that anyhow.
A possible moveset using attacks she actually uses might be something like:
B: Phazon Spray - An attack that focuses a spray of phazon wherever you tilt the controller. Can be charged briefly for a concentrated spray, but not long.
B-Up: Echoes - Three Dark Samuses emerge from the current one, each going in random directions for a few seconds. Does minimal damage, but spectacular as a distraction to help escape opponents safely.
B-Side: Boost Ball - Exactly what is says on the tin, turns into morph ball form and makes a beeline across the stage that is capable of causing stun. Takes a moment to stop, though.
B-Down: Phazon Eruption - I don't know what to call this, but she has an attack where the ground below her erupts with a very damaging light that's charged with phazon. It's that.
Final Smash: Prime - Dark Samus sheds her Phazon Suit to become Metroid Prime, who is invincible and attacks by launching Phazon across the stage. This can either be used strategically to make damaging puddles that last for a brief period, or used to 'corrupt' enemies, doing quick and constant damage until they can fight it off by attacking or running. If they don't eliminate it quick enough, the sheer power of the Phazon will overcome them and cause them to fly off into the border.