To that I raise you Yuri's combos on bosses and Estelle's Eternal Support + Force Field.
If you get directly hit with Zaude boss's hi-ougi in Unknown, the only two characters known to be able to survive it without using any artes/OL4 is Karol and Estelle. (And it's only _sometimes_ that Estelle survives it. Karol's survivability for that is 100%.)
I don't use Judith because as others had said, she's a soloer and does not contribute well to the party. Repede is good for his items usage but I never found much problems that Raven and Estelle couldn't heal through. I used Karol in replace of Estelle once in awhile but I got so used to having a primary healer character in my party from other jrpgs that I had to have Estelle no matter what despite her poor AI.
And I disagree about Raven having the lowest damage output. His spells can be useful and damaging when paired with Rita. The two of them make a really good team. On my third playthrough against the final boss second form, I controlled Yuri for the sake of the SM. All I did was just stand there in amazement when Rita, Raven and Estelle were unleashing spells after spells on the boss till he died and he did not even lay a single finger on my team. They were making about 100+ combos before Raven went and break it with his constant Time Stop. It was an amazing battle, despite me having to restart the game for the SM.
"To that I raise you Yuri's combos on bosses and Estelle's Eternal Support + Force Field."
Hope you are really good at keeping the combo going then, because on unknown, Yuri's terrible defense means he is going to die a lot. As for Estelle's gimmick or glitch or whatever you want to call it (which I think takes the fun out of battle if there is no danger in losing), good luck getting it to hit before a boss' attack kills her again and again. --- Xbox gametag = StrikeNinja24 "I am the Milkman. My milk is delicious."
I recycle through all the characters pretty frequently. o_o;;
However, my best party is probably- Yuri, Rita, Judith, Raven
Karol hasn't gotten his uber healing spell yet... but I still end up using him often because he still heals better than Estelle, and Nice Recovery Smash is extremely useful against annoying bosses.
If I'm not using Judith, I'm using Repede.
I use Estelle for battles where I need two healers, and Rita rarely leaves my party because she's amazing. If I ever get into a tight spot in battle, I can whip out O.L. + Tidal Wave to stall for time while everyone else gets back up on their feet.