I'd say DA and Arnold would receive a Lot of development in this episode concept. Especially since the ship became canon in Cracks a Yolk, and they were the group stranded in Canada in The Frizz Connection.
It'd be interesting how this fic would portray Ralphie and Jyoti. They're my favorite ship from earlier RA, but it somehow died down in Season 3 (similar to how Carlos and Dorothy Ann, the show's longest-running ship, just kinda ended around Season 4 of MSB).