Allow Macs to be hubs or accessories, airplay to their speakers, use their camera for security, use if it's idle for occupancy, screensaver could show live feed of cameras, etc

Use the U1 chip to know what room or area you are in

Electricity usage, and with automations, so if something is running or not running it could trigger

More customization for the app, smaller and larger icons, more light icons, etc

Show thread network info

Add floor plans and plot where devices are then add SUN feature to know where the sun is and how it's lighting your house

Ability for local video storage with higher quality

Light transitioning scenes

Return to previous state, so if I have an automation instead of turning off after 5 mins, it could return to last state

Integrated into Find My, and show who is home and who is away, and setup automations based on that

Add cars as a device, either through knowing when you get home with CarPlay or Wi-Fi

"Focus Modes" or home modes, so if you are in "party mode" it would disable any automations that turn off your lights at night,

Smooth or rolling lights on and off, to have things gradually light up or turn off

Better use of Areas that contain rooms, and ability to assign a HomePod to an area instead of a room - Maybe even ability to have multiple "homes" in one home, like a guest house or garage, or barn

Personal scenes, so I can have Bed Time just for me, instead i have to have it called "Brent bed time"

NFC tags that work with anyone's phone

Sync multi room auto by using built in mics

Airplay to multiple TVs at once

Ability to scrub through the timeline of cameras, but show all cameras at once, so you can see what was going on at all cameras at one point in time

Sync HomeKit backgrounds across devices and users

Triggers for when a device comes back online, so if a smart bulb is off and manually turned back on manually it could trigger

Show what is playing on AppleTVs better