As for the lifetime annotations, we could be extending lifetime elision to more places, including to struct definitions, if people come up with rules that are easy enough to understand. I'd probably be for it, but there are others who think that if you go too far toward removing lifetime annotations then you actually make programs more difficult to understand and the language harder to teach. But that was also the argument against our current lifetime elision rules, which are pretty fantastic in retrospect, so I'm not particularly swayed.