A screen thats both sharper and more vibrant would easily make up for minor differences in brightness and contrast.
That said, there only is acting like one ROG Ally storage option, also a 512GB SSD.
A more clear-cut advantage for the ROG Ally is game compatibility.
Oh ya, Steam.
A bit like how the Steam Deck bakes in FSR at the OS level, for the same purpose.
The Steam Deck went the custom-built AMD route, allowing it run modern games for longer.

The Steam Deck, remember, employs Zen 2 and RDNA 2.
Or how much youd have to pay for the privilege.
Thats why its probably not worth gettingtooexcited about the ROG Ally just yet.
Still, at least we wont have to wait long to find out more.