I'm sticking with the default ones, they seem to be by far the best. Symbols beside them are gold, so I'm guessing they're at max rank.
If you're not playing on hard, changing the heal/defense setting to "when over 75%" is enough for 95% of the fights (so far for me) and in the other 5% you'll just have to manually use Life Bottles lots of them.
Sometimes, different titles will teach you different artes, so it's still beneficial to switch between them.