Quote Originally Posted by Tyreal
Not only that but we also know that Shanks will probably end up sidding with White Beard/Luffy/Dragon as well based off of the fact that Shanks stopped one of the other Emporers from stopping White Beard going to war with the Marines. IMO the only thing the marines really have going for them is numbers, and I'm sure everyone is aware that even an infinite amount of faceless and nameless grunts are useless in most Shonen manga/anime.
Well, the marines aren't all faceless and nameless grunts. It wouldn't be too much to assume that a lot of marines of Captain rank are pretty strong. Considering that Smoker was leagues above Luffy on their first encounter, it wouldn't be too much to make a parallel between Smoker-Luffy and Garp-Roger. Garp was known for cornering Roger many times, and I see Smoker being that thing for Luffy at one point or another.

But aside from Smoker, I assume that yes, other Captains are at least as battle ready as a lot of hardened pirates. Not to mention things that rank higher than Captain.