No, Leon's campaign isn't short on ammo once you learn the "cover recovers stamina, stamina is used for melee attacks/dodges. Melee attack/dodge nearly everything." This is one of those "the campaign doesn't explain the mechancis" thing.
But Leon's campaign does have issues in regards to set-piece design. But that's probably the best playing one.
The problem with the campaign is:
-QTE's
-Gunshot enemies staggering you. This isn't like Lost Planet so on higher difficulties you'll be trying to get up and one of the gun enemies (of which there are many) will stagger you/reroll you.
-Set pieces aren't fun
-Chris' campaign is FUCKING TERRIBLE. One of the worst shooter campaigns I've played in years
-Jake isn't really that interesting and a waste of time when they could've focused on Sherry. But
had to be tied in since they painted themselves into a wall by killing Mary Sue Antagonist last outing. :/
-Ada's campaign isn't that great, double so if you're an Ada fan.
Yeah, it's about 20 hours or so long. I didn't really time it but it felt like forever because none of it was fun, which is really crazy because it was Capcom... but I guess Capcom doesn't have that spark anymore.
Seriously though, dude: I bought the game
two times once on PS3 and once on Steam sale. I can't muster the effort to go through the campaign a second time/PC because it's
that bad. :/