Some of the new updates include the 2015 stud shooter, the new 3M axle with a standard stopper, the axe blades for 2015 Gali and Skull Basher, the stormerangs for 2015 Pohatu, the new 2016 gear piece with a pin hole, and the skull ribcage piece. The article includes a PDF listing off all of the new parts; I’ll post pictures when I can.
When it comes to constraction, LDD generally adds on the pieces that are the most compatible with others first; due to that an eyestalk would be added before an even more specialized head piece. At least an eyestalk has a technic pinhole that allows it to be easily added to other surfaces.
Yeah, as far as I understand, Lego released an official statement on how the program was getting discontinued altogether. Seems as though that was either a false quotation, or that they reconsidered their decision.
Honestly I think the reason as to why the 2015 head and masks werent included is due to the fact that the devs are still figuring out the odd attachment point