Good job. One of the best race changes I have seen. Buttons are all lined up properly and tootip descriptions are well written. I also like how you used "Old Horde" units such as Forest Trolls and Ogres for the Orc clan encountered.
Just a few suggestions and points to clarify:
1). I'm not really an expert on Gnoll culture but I find it odd that Fang and the Den Mother speak in Common properly. I understand they're the high ranking members of their tribe but try to lower their language proficiency a little bit, particularly Fang. For example, he could refer to himself in third person instead of using adjectives like I and me.
2). Fang and the Den Mother kind of received the Emissary too warmly. I know they're not supposed to be completely savage but try to make their conversation along the lines of "Human give Fang reason why Fang not kill human" or you can have the emissary start at a low price with Fang demanding more.
3). Make Den Mother and her associates invulnerable so that player won't be able to kill them for the lulz

You can also make players unable to return to them afterwards.
4). The Stormreaver units seem kind of misplaced considering that they're mostly dead or stranded out farther in the sea. If you want to keep these units there, just omit the "Stormreaver" part from their unit names.
5). The Dalaran allies end up going back and forth the teleporter. The Archmages' Mass teleport makes it worse so maybe you can deactivate it in this instance. Try to make an interaction between Antonidas and Fang even just a dialogue instead of a cinematic. For example: Fang: "Fang and friends here to help human mages. Better get gold ready", Antonidas: Reinforcements at last! Help us drive back these wretches and you'll get you're reward.
6). The Human and Undead buildings don't mesh too well together because they have unique ways of getting built. Peasants building undead buildings doesn't look right. I suggest you just stick to the undead buildings and acolytes just like the Cult of the Damned in Arthas' early campaign stages in ROC.