These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Good Bad Bug: There are two particularly famous ones. The first being the "Jump Cast" glitch where by jumping and then rapidly shortcutting to a spell, the magic user you're playing as would rapidly cast said spell for little cost, making certain battles much easier. The other is the "Move Scroll" glitch where by using the scroll feature on your skill lists when they had more than one page, allowed you to access attacks and spells that the character normally wouldn't be able to use. Having Reid with Prism Sword for example, a spell which is only usable by certain bosses. Sadly, the first glitch was fixed in the PSP port, but the second one remained, surprisingly.
Growing the Beard: This is where the Tales series really started to pick up, particularly with the battle system. Things were sped up considerably and all spells are now performed in real time. The game also introduced a degree of character customization in the Craymel system, two worlds with considerably different world maps, and much more character development. Tales of Symphonia is a much more obvious example of beard-growing, but it owes a lot to Eternia.
Porting Disaster: While not a disaster per say, the EU version of the PSP port made one great mistake—Some of the voice clips got mixed up, resulting in a nice load of Narm during some cutscenes.
So Bad, It's Good}: The voice acting in the EU version of the game ranges from "They at least sound like they're trying" (Reid and Meredy), to downright They Just Didn't Care territory (nearly everyone else, with Farah being the worst offender.) This is very funny and hammy.
Actually, part of the problem is that the AI's not very good at controlling her. She tends to dart in dart out, and doesn't always use the right abilities. Plus, she needs someone like Reid serving as a distraction.
What Measure Is a Non-Badass?: An in-universe example in the anime. Marone dislikes Farah for supposedly slowing Reid down, calling her an "all-talk woman". She gets over it.