On Tales games, I try to unlock the hardest difficulties as soon as possible. You usually unlock these by battling a lot, so sometimes I grind a lot just to get the difficulties.
Some Tales fans tell me I am insane, but honestly I just do it to have a failsafe for final bosses. Usually when a boss is too hard, it's enough to lower the difficulty to be able to beat him ^-^;;. The only time I 100%'d a Tales game in the hardest difficulty was Xillia 2, but usually I have to tone it down at least one level. I never have to tone down too much, normally I can do all boss battles in Hard or even Chaos, but in Xillia 1 I had to tune it down to normal because that final boss was really annoying.