Hiya Maisyn!
Nightborne and Zandalari/troll RP are definitely places where we can improve. Rumakari is MG-Horde based and it is small, and I’m not sure if it is still active. There is also Darkspear Revolutionaries which may be the same group of people. Link here:
There is a Shal’dorei discord which I recommend joining. Although it is not based on MG Horde, conversing with other nightborne players will help you build your network and give you some ideas to work with on home soil.
I thoroughly applaud your approach of “if it doesn’t exist, I’ll create it myself.” We need more people like you! The world is your oyster on MG Horde. We will support you, in whatever you want to make here.
There is definitely interest for RP-PvP. As not many guilds are doing this, there is ‘potential’ in the market, so to speak.