Here are a few ideas / suggestions that would be cool to see in the game.
New brawl areas: The Hidden World, Dragon training academy, Shellfire shipwreck, Dragos Bewilderbeast ice flow, Purple Death island, Screaming Death caves, New Berk, Dragons Edge academy.
New brawl / champion dragons including Light Fury for VIPS only
Defend Berk: being able to fight Dragos battle dragons and Bewilderbeast.
Being able to equip titan skins on and off.
More dragons for Light Fury to search for.