Answering a month late, my bad.

Avian, Arryn and Stahl always get together for time together during the winter holidays no matter what even though they live in different regions (and Stahl and Arryn are legally separated but on good terms now. Loredrop!)

Of the DLC? Kieran and Carmine were my faves no question. For the main game? The climax at Area Zero. The entire core cast of friends was an absolute delight

Pokemon SV are kinda frustrating because its some of the most fun i've had playing the game but the performance issues are still a major main in the ass years later.

Avian was originaly a mean spirit self-parody of the aspects of myself i hated. So honestly? nothing would change in the slightest

Arryn is already a champ in Paldea, tho she just uses the Terastal phenomenon to level the playing field.

Avian... out of all the pokemon he's collected over the years all of them serve a different purpose for different tasks so there isn;t an "ultimate" team. Though if he had to pick out of 6 out of the ones he has:
Charizard (kind of a mandatory pick as his lifelong ace and friend)
Silvally (Water Memory)
Roserade
Togekiss
Espeon
Dragapult

Stahl - Leave
Arryn - Pull out a bigger, scarier ghost
Avian - Talk to them and make them cry when trying to relate to them

All of them have survived br*ish food

Stahl has other people run his social media for him. He is blissfully unaware of the chronically online.

Arryn has an instagram where she posts pics/vids of her pokemon and workout routines. She has a lot of followers, half join for pics of legendary pokemon she chases for fun and the other half stay for thirst traps and ab pics.

Avian has a work twitter as a gym leader. despite this he was unverified back when verification meant a damn

Avian is fluent in french/kalosian but doesn't know it

Avian: Regular exercise and wellness checks. Avian will literally host meetings with his team even on zoom if he has to, sit them around a table to discuss strategy and collaborative action then follow it with an hour of training sessions and sparring if need be.

Stahl: Has others do it for him.

Arryn: Travel and exploration paired, sparing with each other and getting into fist fights with legendaries.

Arryn is one of the members of the Galaxy Team from PL:A that went missing before the player arrived. This is canon.

Avian is Dripless

Designated driver: Stahl, he has the endurance to drive 6+ hours and kind of needs to be in control.

Navigator: Arryn, she has an excellent sense of direction and overall perception and special awareness.

Snack Distributor: Avian is very good at making sure everyone (other than himself) is well fed and hydrated.

To varying degrees, deal with it.

Avian: Suffer in silence

Arryn: Leave and take the stairs

Stahl: Forcibly evict them from said elevator

Arryn would 100% thrive, Stahl would not. Avian would either singlehandedly rebuild civilisation or die before the first day ended.