Support for simple animation.
Example: Show/hide a slide or push menu

This would enhance a demo and engage prospects that are familar with common application patterns.

Need Little bit tapping/hover effect on list/buttons/links during presentation to client. Its give an actual working product feel and help to make decision.

rollover, mouseover

Define a scrollable area within an artboard

This provides real-world app use cases, such as a table, slideshow, or iOS dropdown lists.

Support to import a video or animated GIFs to simulate animations or even playable video.

Provide the ability to change multiple objects/elements within a document and/or across artboards.

Example: Ability to increase font size within a button across all artboards (without multi-select)
This is similar to increasing font size within a repeatable grid—all increase.

Another example: replace/swap a theme color throughout the document.

Similar to Edge Reflow, it would be great to have the ability to prototype responsive design ideas with a fluid, flexible canvas. Web designers need a good tool for this there really isn't anything out there to test out responsive design solutions.

An ability to drag out persistent guides to an artboard and have other objects snap to it

Ability to create and customise content carousels or slideshow type scrollable areas.

Currently there is a "scroll" feature in build, but it seems to be about page scroll and up/down scrollable areas.

Need line/border styling as dotted and dash

I remember, I have seen this presentation at Adobe MAX 2015. Where we can use dummy / Sample data for content such as Name, city, country etc (Please also think to add lorem ipsum dummy paragraph if possible).

I would love to know, is there any plan to integrate that concept in near future. Its a really great functionality and time consuming important feature for us.

Ref - Design with Data - Adobe MAX 2015 - Sneak Peeks:
https://www.youtube.com/watch?v=e8ebPSJR3U0

Add basic text transform like there is in Illustrator to make it easier and faster for developers to code your designs. Our developers have to waist time retyping text for layouts that have already been designed. At least basic uppercase and lowercase.

1. Ability to have a single object (or group) break out of its artboard and cross multiple artboards within a single prototype. The simplest use case is the creation of a global navigation bar that spans across multiple screens. This object's interactive elements would also work across multiple screens as well, and any edits to this object would update across the rest of the screens.

2. Easy interaction management and editing. Also provides consistency with consistent elements within an experience.

It would be great to Export Prototypes as pure HTML Projects. I am working a lot on Multiscreen apps, where I mostly use Serveal Webcontainers Running on several Screens, to develop those Applications.

Provide the ability to reposition/move images within masks.

If you make a mask via Object > Mask With Shape, then you can double-click into it to reposition the image (or other content) within the mask.

However, if you drag an image file onto a shape, it gets masked by the shape and you CANNOT reposition the image or adjust the cropping. It is auto-cropped to fill the shape when you resize it, but you don't currently get full control of the cropping.

This would make it easier to use the assets created in other Adobe applications.

In order to full use this as a UX professional, I would have to have the ability to include gestures, most critically for handing a stakeholder a wireframe or design. Gestural swipes, two-finger zoom, force-touch, etc. Otherwise I don't think too many experience UX professionals will be able to properly communicate core functionality and the behavioral imperatives incumbent to the process.

Import Illustrator file with options to select layers and/or artboards.

This would increase ease of use and workflow, so a user is not always switching between apps.

It would help a great deal if Character Styles can be named. Right now it is tough managing them and knowing which is which.

Global rulers for the x/y axis.

Option to link objects (or generate smart objects) when pasted from a PSD or AI source to maintain a reference.

This would provide a simple method for single or multiple object updates (beyond the CC Design Libraries integration)—saving time and ensuring all objects are the most current.

Example: Revision to a microphone icon via Illustrator, which is used across 20 artboards