Yes, I know the book is actually The Three Musketeers, but the system works better with four and anyway d'Artagnan gets his commission by the end of the book. I read an abridged version dozens of times in second grade and the original version still works for me, though it's got its hokey bits and our heroes are actually defending a pair of royal idiots and plotting against the only intelligent and conscientious person in the ruling circle. But like a good Sherlock Holmes story, you read it for the giveaway scenes and not the plot anyway.
Each of the Musketeers represents an aspect of the male personality. There's some overlapping between the characters of course but each has a distinct trait that Alexander Dumas plays up in order to streamline the characterization. The idea of the classification system is to figure out which wine would each Musketeer bring to the table. Admittedly a somewhat chauvinistic approach towards wine, so sue me, but I never read Little Women.
Athos is the true hero of the book, at any rate my favorite. Dark, brooding, tragic though redeemed by his sense of honor. Aristocratic by breed and carriage, Athos is a leader without unduly trying to be one. To me, he's pure Burgundy.
Porthos is the big, macho man of the group, with no little vanity. They're all fighters, but he's the most physical, the one most likely to use his fist rather than a sword. At the table, though, he's a gourmand, a man who appreciates a hearty meal and can keep it up all night. To me, he's a very bretty wine, all horse sweat though conscious of his appearance. I think Porthos has a huge supply of Rhone reds, mostly Hermitage and Chateauneuf.
Aramis is all about romance and seduction and a bit feminine and vain. Forget the religious stance, it's just an act to get some pussy. He's just as hedonistic as Porthos though you imagine he watches his waistline more carefully. In short, Champagne.
In a way, d'Artagnan has a little of all his friends, because Dumas was canny enough to play on the readers' expectations to have the young man grow through his experiences with his older friends. Thus he's the most round character and he's got the romantic flair of Aramis, the physical bravery of Porthos and the nobility of Athos. But most of all he's a leader and a bit of a capitalist. D'Artagnan will climb up the ladder all the way to the top, in a manner that Athos never would. Anyway, this Musketeer might hail from Gascony but to me he's all Bordeaux.