Abyss and Vesperia are waaay better than Symphonia. I can see preferring the plot/characters but the battle systems are much more improved.
It's still worth playing Abyss and Vesperia. It's not like one outclasses the other. At least, the changes in the battle system from TotA->ToV aren't as dramatic as the ones from ToS -> TotA.
EDIT: And by which I mean it's not going to be difficult going from one to the other; I know some people who played TotA first and then ToS, and disliked the battle system a lot.
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You have no time to ponder such questions, as Link has just grabbed a Smash Ball.
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