I've finally had the chance to read through the concept and this is some good stuff
My favorite is probably the way you implemented the horns of Angmar, it is a perfect offensive spell, allowing for extreme early game agression giving a advantage but that becomes less strong on the long game. Fell wind needs some work however, in edain movement is key and therefore the ability to hinder movement is extremely powerful, too powerful for a tier 1 spell. I would recommend this be reconsidered.
I'm not a huge fans of the rest of the powers, the temporary scavenger doesn't feel right. Sure the lower class of Angmar could be prone to it, but what of the Men of Carn Dum? Would they really lower themselves to pillaging? It could work and be interesting but I don't personally support that one.
If outbreak is to be recentered around a single barow lair it will also require a power boost, as settlement plots are not always available and barrow wights are not always the first choice. Finally the central spellbook feels a bit bland being a simple power boost
Apart from that your proposal are always a pleasure to read, albeit a lengthy task
One suggestion I would put forward is to emphasize more the actual game play effect of each suggestion. It is something hard to discern what the suggested power or ability's effect is in gameplay terms. Keep up the good work
P.S. I also like the image proposal for Rogash.