I'll switch a gig on the grip of a handshake if it doesn't feel right!
[Only a drummer who practices paradiddles with both hands leading can make that stuff up]
Seriously though, I am exclusively trad at the moment. My only matched grip is striking the high tom with my crossstick during a bossa nova or samba groove. Perhaps if I practiced more regularly I would trend toward using both.
(a) Match looks cooler. You get that fat gospel chops snare sound too. You get to angle the snare toward you, which makes the total kit footprint smaller. You also get to add extra toms just to the right of the hihat (on a right-handed set) without worrying about playability issues (the common issue with the butt end of trad player's stick).
Trad grip puts the work in your elbow and wrist, and thumb, thereby completely eliminating the stress on the shoulder and neck. But trad grip is harder to get a meatier rim shot sound, which is why trad players tend more to be vegetarian. Trad grip players can quickly switch from trad to cross-stick. Trad is short for 'traditional', so players have the comfort of knowing they came first. Trad often calls for an angling of the snare away from you, and in the process, puts you at risk for injuring your leg against the snare stand cradle or the throwoff, especially if it's a chunky throwoff.
(b) Yes
(c) Yes
EDIT: Trad grip players get to fondle the side of a snare in the middle of a 2-4 backbeat. Especially pleasing if it's a high-gloss lacquer stained maple finish.