It will be neat to have the option of printing the comments along with the design

I'd like to see an overview of all the activities and comments on all of the pages within a document that is shared. Otherwise there's quite a good possibility of missing some.

Something like Invision has would be great:
https://support.invisionapp.com/hc/en-us/articles/115000633426-Activity-Stream

When creating a prototype link - if you could set an image compression level that would save stakeholders waiting for an age when waiting to viewing the prototype. In a number of cases actually using the prototype link as a presentation tool, it is just not efficient enough to be consistently viable as a choice.

It would be really good if one could choose if the comments should we visible for other users or not.
Sometimes there is value in the users not seeing each others comments and sometimes there is good to be able to 'discuss' the mockups.

Faster syncing of pc/mac work in xd to mobilr

Takes way too long for existing and new xd files to show up in creative cloud to see on iOS.

Currently the View of a XD file in the Webinterface inside Creative Cloud is pretty bare.

It would be great, to add a rich preview of the file like the on Photoshop or Illustrator Files. This could be split up into different sections like full file Preview, the Prototype view and a view for Developers to extract measures and assets.

This way you automatically get access control to the prototype.

The agency I work for is very particular about archiving internal and external markups. It would be great to have an option to export the "Share Online" markups into an annotated PDF for archiving.

I am about to use it for design prototype for work. As I tested it, I found out the colour between design view and share online result have different colours.
Please check the attached files. I tested with my own file and the examples from adobe.

Allow people to become watchers of a prototype so when the document is updated they could get updates to check it out.

Bonus points if it can highlight what's new.

This would be great because I'm working on something and my manager works remotely and feeding back as i'm working. I'f she and others were notified when it gets updated then it would save me a manual email every time I make a change.

I would like share my prototype in some kind of interactive file, that can works without internet and without any other program, something like a interactive video.

well it doesn't make sense why you can only record the video when someone is on your computer trying out the prototype, and just thinking you should be able to record how someone is using it when they are overseas

Ideally this feature would allow an "export page as PNG" or "export all pages as PNG" function that is available while viewing on the web.

Once a prototype has been shared online, web viewers often need to export full screenshots of specific pages (or all pages). This process currently works fine if the page does not scroll, but does not work if the page is scrollable because part of the page is not visible on the screen.

It would be great to be able to choose the page to view online directly.

When you want to quickly show a certain page in your mockup, or start anywhere else than your designated Home, it can be tedious to click through the prototype as not all the paths are there.
Using the previous/next buttons can be confusing as it depends on how you have spread out the artboards.

For better flow and clarity for the clients, to have artboards names visible at the top of every screen in the public views.

It would be nice if the creator (sharer) of the prototype could add footnotes to the shared prototype, separate from the comments.

eg. if there is a conditional object. this hypothetical object on the page should only be there when the user has a message, I'd like to be able to add a footnote to inform the shareholders on this condition. Footnotes would be used for these function-specific notes, and comments would be used for feedback and discussion.

Include the file name in the shared link to make it easier to keep track of multiple XD prototypes.