A few add-ons to the brilliant punch list you got going there :)

1. Error states: Whether it's form validation or a warning related to some action, designer and writers must not leave this as an after thought to the developers

2. Empty states: Taking the idea of 'Empty search page" further, designers should consider and craft appropriate empty screens for all kinds of scenarios

3. Micro-interactions: The designs come to life when they flow from one state to other with the right transitions, animations and micro-interactions. So often, this is left as an after thought after the development has delivered an Alpha release for the designers and other stakeholders to review.

4. Guidelines for responsiveness: In more complex layouts, how the navigation or content will respond to different screen sizes must be considered deeply before the handoff of assets to developers

5. Optimized images and videos: Designers love to work in Hi-fidelity but often it's not a good idea to handoff 4k assets to developers, assuming they'll know how to optimize and use them.