Titania should be weaponless and used as your tank until everyone else catches up, but yeah, she's useful when everyone else is near her level. You can also try letting her get the final hits on some bosses and she won't waste experience like if she kills normal enemies.
Also, keep Ike around the same level as everyone else. It's hard to resist using him to beat everyone silly, but it's worth it in the end!
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"Duel audio? You mean like rap battles?" - termina_rzident
KrahenProphet and Kana are on opposite ends of the Awesome Spectrum.