Hmm I don't know much about Leon, so I won't jump into conclusions, but I heard you say he is safley above Snake in physical condition. Not saying your wrong or anything, but just give me some facts about what he has done, I'll just give some of Snake's for the heck of it...
He defeated Cyborg Ninja unarmed, which had a suit of steel (which Snake punched on like a pillow, and actually wounded Fox through the suit). Fox could also move so fast he was barley visible, and yet Snake overcame him...
Snake could dodge bullets from an assault rifle from point blank range...
Outran a Vulcan canon fire when having a Stinger missilelauncher/rocketlauncher in his hand...
Metal Gear Rex was as high as a building, a pretty tall building that is. Snake could jump up to it's knees in one jump, which having a rocket launcher in his hand...
Dodging a bullet from a scout knife, when he didn't even know Olga was going to shoot. (It was a knife, he could not expect it, also, he had her as a prisoner, so he wouldn't have expected it). This means he has some damn good reflexes.
He dodged Revolver Ocelot's bullet (who is so damn skilled it's ridicilous) when he surprised attacked Snake. Also speaks for his reflexes and his speed...
If Leon is better than that it would be pretty cool though, could you state why?