First of all, the STG-45 is in game thanks to the efforts of Jorge2125. Here are some pictures of that, since you're all probably more concerned with that than anything else in this announcement. It will be wielded by Panzer Elite troops.
As for the Panzer Elite itself, I do not consider it to be a separate army from the Wehrmacht. In fact, like the Wehrmacht, it encompasses units from the Heer and SS. These units are just of a much higher quality, and are generally given more favor by the Fuhrer. For instance, they have access to newer weapons, such as the E-series Panzers. Which ones exactly have yet to be decided, though Wird is working on the E-50 right now, if I am not mistaken.
The playing style of the Panzer Elite is flexible. It's Panzer Grenadier units have only 5 men to begin with, less than any other faction, but they are very versatile and powerful. There are no Assault Grenadiers anymore, because Panzer Grenadiers now fill both a defensive and offensive role. They can do this because they have a variable fire function on their weaponry. They can fire full automatic, or they can switch their guns to fire semi-automatically. They do both functions just as well as any other faction. "So what's the downside? Won't they be OP the way they are?", you may ask. They certainly would be, if the Panzer Elite didn't also have high population requirements for its units as well as exorbitant infantry costs.
It should also be noted that E-series Panzers are the best armor available to any faction, but they have been implemented so recently that it takes much longer to assemble them because their workings are unfamiliar to workers. They are also of only a limited availability. However, E-Panzers are somewhat cheap for what they bring to the battlefield, and they have very low upkeep costs.
Remember, the Panzer Elite is literally just a collection of the Fuhrer's favorite and most elite units, not a formal organization. All the units in the faction are merely able to be given the moniker "elite", which binds them together. This is shown by their doctrines, which take the form of support from individual super elite divisions. The first of these I will reveal is the Großdeutschland Division, which gives you access to advanced Panzer Elite units faster and in higher quantities.
With that information, I shall conclude this news bulletin. I hope this answered some of your questions about this mod and its long term goals.
P.S. Some changes have been made to the mod page, so feel free to tell me what you think.