I mean with personas and other than the MC, cause he was a badass and was obviously the strongest!

The robot lady.

Aigis, on account of being a robot with multiple guns. Then probably Akihiko.

Fuuka, obviously.

Aigis, followed by Mitsuru probably, since she had her Persona the longest out of anyone.

Whatever, I don't care how long you had your Persona, if you're just going to cast charm then you need to get the fuck out of my party.

@bigjeffrey: BIASED.

EDIT: My answer is whatever P3 character has the highest win-to-loss ratio in P4A. Because Math.

Eff first posts, this is the only real answer!

When Mitsuru actually got around to casting useful spells, however, I found that she hit harder than anyone else with the possible exception of the MC. I had her dealing damage for most of the final boss battle.

I never had her cast anything useful lol

Mind charge combined with bufudyne dealt a ton of damage to most things.

Aigis is probably the best bet, she can deal some heavy damage. In the end you really just have to overpower the MC.

Damn it the OP asked "In storyline, which party member was the strongest?"

What's with all the gameplay chatter? Come on people!

So not including the MC I believe it goes Aigis > Mitsuru > Akihiko > Shinji > The rest.

Aigis's feats outshine Mitsuru despite impressive showings from both at various points in the P3 time-line and Mitsuru's magical power and strategical intelligence beats Akihiko's physical abilities and his rush-down, head on nature. Shinji, despite his issues has the strength and experience over the new guys. Everyone else are on the same level, though I may place the kid and the dog at the bottom because they don't really have anything going for them defensively. They seem like glass cannons that wouldn't pack that big of punch compared to the top 3.