More color choices
For a device that's typically worn in public, it's fairly surprising that Apple only sells AirPods in once color option. Rivals like Samsung offer more choice; its newly announced Galaxy Buds (pictured above) are available in white, black, and yellow, whereas the AirPods are only sold in white. It would be interesting to see Apple launch AirPods in a variety of colors that match the iPhone XR.
Hands-free Siri
Apple should put the AirPods' dual beam-forming microphones to additional use by making it possible to summon Siri without having to tap an earbud. Given the AirPods' sleek, button-less design it would feel more natural to activate Siri by speaking rather than tapping.
It looks like Apple might bring this feature to its wireless headphones eventually. Bloomberg reported last year that the "Hey Siri" functionality would be available on Apple's next version of AirPods, while 9to5Mac recently spotted a setup screen in iOS 12.2 for enabling the feature on AirPods.
Local storage
Apple has been making an effort to turn the Apple Watch into an independent device rather than an iPhone companion in recent years, and it wouldn't be surprising to see it take a similar direction with AirPods.
Apple introduced cellular connectivity to the Apple Watch with the Series 3 model, for example, which enables it to make calls independently of your iPhone. By adding local storage to the AirPods, Apple would make it possible to store music directly on the headphones themselves, eliminating the need to stream tunes from a nearby iPhone. Earbuds like the Samsung Gear IconX and Bragi Dash Pro both offer this feature.
Water resistance
The iPhone is water-resistant, as is the Apple Watch, so it feels like it's only be a matter of time before the AirPods are too. It's especially useful for a device like the AirPods that's worn on the body — perhaps outside during a commute — that could potentially get wet from rain or snow. There's a fair chance we'll see this in Apple's next-generation AirPods, as Bloomberg also reports that Apple is planning to add such capabilities in an upcoming model.