Uhm...
You know nothing of Nathan then
Nathan beats everything.
Mal beats everything.
They both beat everything.
A vampire won't stop Nathan.
A vampire won't stop Mal.
A less-handsome-than-Nathan guy won't stop Nathan.
A less-handsome-than-Nathan guy won't stop Mal.

Do you see where I'm going with this?
Nathan/Mal is the God of Awesome. 
He is unbeatable

He also owns a starship and a crew and the loyalty of everyone. River's a bit odd, but Simon listens to Mal, so Mal > River

[img]http://images5.fanpop.com/image/photos/26200000/Malcolm-Reynolds-malcolm-reynolds-26243909-2086-2560.jpg[/img]