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.
YMMV: Phantasy Star Universe
Abridged Arena Array: Throughout PSU's run, players have sought out the Free Missions with the most efficient EXP gain. The lobbies for those missions would be accordingly packed full as well. In Vanilla PSU, this first happened to "Plains Overlord," then to "The Mad Beasts," then to "Endrum Remnants." When AotI was released, this honor went to "White Beast," and remained so whenever an event wasn't going on—to the point that PSU itself was derisively nicknamed "White Beast Universe" as no one seemed interested in running any of the other missions in the game.
This tendency prompted Sega to introduce the "GUARDIANS Boost Road," encouraging players to run chains of other missions for greater gains compared to spamming a single mission over and over.
Canon Sue: Emilia from Phantasy Star Portable 2. At first she's just a lazy girl with a spirit trapped inside her. As you learn more about her, however, you find out that she's a genius practically from birth, crucial to a massive supercomputer, can make calculations that strain even the robotic CASTs, designed Lou's parts as scribbled notes while she was bored, and otherwise is pretty unstoppable at anything that requires her mind, all as a teenager. She even has a tragic backstory, that requires other characters acting out of character to even happen. Neither Obel nor Laia seem like the types to greenlight Project Tenma.
Perhaps the ones who greenlighted Project Tenma are the same ones who deemed Vivienne (who was an unknowing and unwilling Illuminus spy)and the player character (For going after her) traitors.
Moral Event Horizon: Light Master Dohgi Mikuna is revealed to have crossed this a long time ago when Ethan discovers that Dohgi had been using Mirei Mikuna's gifts of divination for rogues and other criminals, receiving payments for doing so. Long before that, Dohgi placed a Mark of Light on Karen, Mirei's twin sister, to bolster Mirei's vitality; the Mark saps Karen of her abilities, which leaves her unable to use TECHNICs. During Episode 1, Doghi attempts to finish the job by sacrificing Karen's life in order to prolong Mirei's. Mirei tries to stop him, but is met with a powerful Technic that kills her.
"Stop Having Fun" Guys: You don't have to do much to get booted from a party. Especially when you're at the end boxes in certain missions.