Best (going full hipster here) would be Atelier Escha and Logy Alchemists of the Dusk Sky. Mostly due to the fact that being the first Atelier game I ever played it was something very different from what I usually get in RPGs, loved the time mechanic, the battle system simple yet engaging, the alchemy was a great element as well, being able to craft and power up items and equipment depending on the material and the effects each of them give, artstyle was great, the soundtrack is just glorious. And I definitely enjoyed the more personal story instead of being an epic adventure.
Honorable mention would go to Tales of Vesperia, another solid Tales experience and probably the last one that was excellent in the series.
Worst goes to Tales of Symphonia Dawn of the New World. Not a bad game per say, but definitely a terrible sequel and sub par Tales game (there is a reason why is not even considered a main title) even more so when the original is my favorite RPG of all time, seeing this game messing up some of the characters and the story as a whole was just painful, the new characters don't really bring anything worthwhile either, plus the mediocre remixes and ok new tracks makes for a forgettable soundtrack, combat felt a bit more stiff and other Tales games too, in general just a dissapointment for me on every aspect.
