Great wish list for WWDC by Steve Troughton-Smith for MacStories. The items that resonate most with me? First and foremost, a terminal environment for iOS:
Much like the file system, for a certain class of user the need for a command-line environment of some kind hasn't gone away as I'm sure Apple had hoped. Now, with Apple's own Shortcuts app, more users than ever are automating tasks on iOS – it makes perfect sense to provide something more for the power users that need it, especially if Xcode for iOS becomes a reality.
Also mentioned that I pine for: much-improved support for USB devices, including external storage, and a “textual” interface to Shortcuts for scripting. He also makes an argument for virtual machine support in iOS, but I think that’s pretty unlikely (though would be welcome).