Answer: Wario is generally considered a much higher tier character then Samus and Dark samus.
Explanation: Wario's tier placement is top 15 at lowest. He has incredible framedata, great combos, great recovery (with bike), and waft (the fart) which is an excellent kill move that can steal games and be comboed into.
Samus isn't a bad character but she is lackluster when compared to wario. Samus's game plan is simply to run away with her projectiles. Shes not the fastest character and can get beat by other zoners or rushdown characters. She's not unplayable, but not the best pick for competitive play.