Unfortunately, I’m not the best person to offer in-depth analysis on fighting games. I know systems well enough to understand them, but when it comes to distilling mechanics down to combo efficiency and timing, I’m completely out of my league. So, if you’re looking for that sort of depth, I probably won’t be able to offer it, but will do my best.
From the outset, Persona 4 Arena is incredibly simple. Attacks are tied to four attack buttons split between your fighter and their Persona. Move sets contain commands for both characters, often times crossing over between the two entities. For example, you might start a combo with your human character, only to have the Persona manifest and continue the attack. From there the Persona disappears or, with the right commands, sticks around a little longer to continue hammering away with other attacks.
This is where things go from simple to complex. Character depth doesn’t come from mastering a character’s every move. Instead, you’re mastering two different characters and focusing more on situational tactics. I’m by no means a master, but fights usually tend to come down to how a particular player handled their character based on a set of circumstances. It’s not just a matter of countering an opponent’s move, but figuring out what to do based on position, how much special energy is built up or your character’s special traits, such as Aigis’s ammo counter. You’ll definitely want to spend time in the Practice and Challenge Modes to get a handle on everything Persona 4 Arena throws at you.
Personas will take damage during a fight, and can "break." While this reduces the amount of stuff you can do in a fight, it doesn’t mean you’re completely out for the count. Instead, it offers a nice puzzle element to every fight.
As someone who isn’t into fighting games but likes Persona, I figured I would like the game, but wouldn’t want to delve into the fighting mechanics as much as I did. I came for the story, but ended up enjoying the mechanics more. Not that the story is bad; I just didn’t like listening to thirty minutes of dialogue for every five minutes of actually fighting. Fortunately (some might even say mercifully), Story Mode isn't mandatory, only part of a bigger, meatier experience.
Persona 4 Arena has the task of serving two masters and should provide just the right experience for both.