Satomine Night
The Power of Z!
I don't think Ash will get a Rockruff because I bet Kukui has one but I hope he interacts with that one a lot. Also, keep TR's annoyance level to a minimum - give them something to do other than bother Ash and Pikachu 24/7.
If the Rockruff is Kukui's, perhaps it will become attached to Ash and decide to accompany him if Ash leaves the island to partake in the Trials. I'll confess, I'm not going to stop hoping Ash gets Rockruff (that is, unless the anime makes it quite clear that Ash won't get one). It and Midday Lycanroc seem like the perfect Ash Pokémon.
I'm all for Lady Lana getting a ton of screentime and focus!! Funny if Suiren is the oldest in the classroom (outside of possibly Kiawe) yet she's the smallest/shortest and looks so cuddly and sensitive. I can see her raising her voice, being the "mother"/"big sister" of the group when it's needed. She's the first to take charge of the situation (probably the first one to act like the leader and tell people what to do if they're physically frightened and don't know what to do.)
This is precisely the kind of interaction I want Lana to have with Ash; he is the kind of boy who would exasperate an older sister, or at least awaken that big sister instinct. ("Great Arceus, this boy needs someone to look after him!") She could be the mediator when the others start bickering, or, as you said, the one who takes charge when the others don't know what to do.
Lillie: Her inability to touch Pokemon is an interesting move. How Alola Vulpix (who only appears on the poster) fits into this will be cool to see; perhaps it's a wild Pokemon that takes a liking to Lillie and follows her around for quite a few episodes. She learns to befriend it with Ash or Mallow's help, and catches it in a Poke Ball. She'd train herself to try growing close with it and they have a connection that is close without her having to physically touch Vulpix.
I would really like to see that, if in fact she ends up with the Alolan Vulpix. Even if she doesn't, I want Ash to help her learn to connect and form a bond with a Pokémon without having to physically touch it. It could lead to some heartwarming moments and speeches about connecting with your Pokémon's heart. I just hope Lillie's inability to touch Pokémon doesn't turn into an ill-treated gag.