What do you think about something like this:

Design mode while smart-object selected can show one more tab at app header with smart-object name. In the appearance panel at the right adds some fields while smart object is selected.

To edit smart-object you should open tab with it and work as before, except that artboards name is the name for different state

And You can place another smart object in a smart object ;)

When I swipe between screens I do not want the header and footer bar to slide with the transition, just the content area. Please create a function for this

It would be nice if there was a way to have multiple versions of a design living in one document. Right now we'll have a v1 wireframe and will be reviewing features for v2. I typically lock that version and then create a new file called v2 and start making changes. Would be nice if they could be linked somehow verses multiple file versions.

Hebrew & Arabic language support for all those who need to make RTL prototypes.

http://g.recordit.co/Y24jefUm5Z.gif

To speed workflow it would be good to have button tool in the sidebar. In the property inspector you'd have the ability to specify the top,bottom, left and right padding. the width of button would dynamically resize as you type the button's label.

I want to have a consistent set of swatches, with the ability to import saved palettes or to share/export a palettes. It would be nice to have access to multiple palettes as well

It would be awesome to have blending modes in the sidebar.

Using XD currently, were other members in team are using sketch.
Not able to deliver required (sketch) file format to front end developers.

Frond end devs are using only sketch to read, since majority are using it.

Option to "export to sketch" would solve the file deliverable problem.

I'd like to have bullet point support in my area text.

I use JustInMind to prototype Web and Mobile apps that I then user-test. The JIM application is less than optimal, but to attract a broader Human Factors / Usability / Design audience you're going to need a lot more than "scrolling."

Interactive elements such as text fields, check boxes, drop-downs, etc. that can all be connected, responding to user inputs as needed, in a manner that replicates a real application in its native environment is what is needed.

I look forward to that day, as your design tools and simple, visual linking paradigm are certainly winners.

Ability to create interactive relationships, like radio inputs, if you select one it deselects the other. Selecting different options can change the outcome when the user hits 'Submit' etc

When you choose font for text, would be good to have some preview about how it'll look.

Add unique CSS properties to object properties.
Things like Margins, Padding and un-even borders are not common for design apps, but it would be great to define them per object in XD, honor them in the design mode, and export them as part of the object css,

As Sketch already do... Possibility to copy css attributes by right clic (like gradient attributes,...) and paste it into a code editor.

Make the editable text area's fully justifiable to mirror publication materials.

I would like to use icon libraries (web fonts) without to install them as fonts in my system. For that it would be great to have the option to use all icons of a downloaded "woff-file" i.e. from the following sites and embed them into the xd project:

materialdesignicons.com
flaticon.com
Google Web Fonts
FontAwesome

Nothing more complected simply add Extract css from design as given in illustrator its very important other wise now day's it's simple to design in XD and very difficult to Develop application from xd assets because of no css export option in it, Please include this.

It would be great with a few more features/interactive animations when you link the pages. More easing options. I guess what I'm saying I would like to have more animations and effects based on what we have on websites and apps to this date.

transition presets

this is very important feature, that will make life of many designers and their clients much better