FFXV covered above by others so I figured I'll just reply to the dock part.
So, the main reason I think a dock is a definite is for ports. I don't imagine every controller will be Bluetooth to a dongle, and I think given current game sizes an ability to add an external HD via a port will also be a must. Not to mention an Ethernet port. So, I think a box that also contains the HDMI out cord is the most elegant solution for how to offer these functionalities for this type of hybrid device.
The secondary reason is marketability. For NX to have literal living room presence as a device and to be marketable as much as possible as a hybrid HH and home console device I believe it needs more than a dongle. A sleek box that the HH clips in to will be able to offer this aesthetic.
Additionally, I think Nintendo will want to differentiate the system from Wii U as much as possible. If the primary method of control is the HH, they don't succeed in that visually as well as they could. That is to say, I no longer believe (as I did prior to the EG/related leak) that the primary controller will have a screen inside. I'm not ruling out the ability to stream HH to dock but I don't believe the HH will be the primary controller for home use. FWIW I think the hybrid nature of the games supports this belief insofar as the HH likely won't be featuring games with asymmetric or two simultaneous separate screen functionality as we saw with Wii U, i.e. the HH version that would be the visually more complicated picture in picture we see with stuff like W101. I doubt that would be the norm for HH games, so I don't think the console games will generally necessarily offer two screen simultaneous functionality.
Finally, while Eurogamer's leak may be from a devkit build, I'm hopeful they wouldn't have leaked it as a major story centering around the dock functionality as it did of they weren't confident this would be the general setup of the final product. With the product slated for release in March, I am hoping they were able to get information about a near final product.