So I decided to make my own post out of a response I recently gave to a different thread. I know the Devs said in the last livestream that they are looking for ideas about what stronghold to make next, and I wanted to get my input in. Either way, if whatever they make is on par with the Yavin stronghold's awesomeness, I will be very happy.
Here are my ideas, in order of preference:
1. Rishi Pirate/Mandalorian Hunting Lodge on a private island.
Think of Shae Vizla's fortress from the Blood Hunt FP. Ideally with plenty of those wooden bridges, definitely with a river (if not more than one) with waterfalls throughout. Incorporating a volcano would have some potential as well. Also I think it would be amazing to have some kind of area (maybe a partially underwater cave, or a separate island) that is accessible only by riding a gondola or raft that you have to interact with, and wait as it takes you there. And I'd really like to see it set at night. That would be a perfect place to show off all those decorations that involve fire, especially the Mandalorian torches/wall sconces that arrived with the last cartel pack.
Oh, and for what it's worth... if the clues dropped in Shadow of Revan and the KotFE announcements are any indication, the new expansion will deal heavily with the dwarf galaxy (the Rishi Maze), and Rishi is the threshold between the Rishi Maze and the known galaxy. I think it would be a logical (and fun) connection to release a stronghold on Rishi later this year to go along with Fallen Empire.
2. Alderaan Manor set high up in the mountains.
I'm imagining something that takes inspiration from Rivendell in the Lord of the Rings and the Hobbit movies. Set on a cliffside, with rivers and waterfalls throughout, and all of the architecture made out of rustic, heavy-looking stone. Maybe with some kind of gazebo right next to a waterfall on the cliff. Here are a few pictures for reference:
http://vignette3.wikia.nocookie.net/saganomringen/images/4/4c/Rivendell-council-the-hobbit-an-unexpected-journey-35430552-2048-866.jpg/revision/latest?cb=20131021205953
http://corecanvas.s3.amazonaws.com/theonering-0188db0e/media/original/50c8e1f704bd5_Ancalagon_GaladrielAtRivendell2.jpg
http://i.imgur.com/WtDI638.jpg
http://images6.fanpop.com/image/photos/35300000/in-rivendell-the-hobbit-an-unexpected-journey-35355363-2048-1152.jpg
https://s-media-cache-ak0.pinimg.com/736x/76/f0/a3/76f0a352169fd4aacdb20c43d3bbd4e1.jpg
http://blog.coldwellbanker.com/wp-content/uploads/2012/10/JMCarrvill-Flickr.png
3. Manaan stronghold with underwater section.
I know this is a popular idea. Manaan is beautiful, as is the music that plays in the background from KOTOR. It's certainly worth considering, although I am less enthusiastic about it than most. While being out at sea is beautiful, endless ocean would get very boring after a while, especially considering the Selkath architecture in Ahto City is very sterile and white-washed.
Also, while everyone seems to be excited about the underwater idea, I'm just not sure how good it would look in execution. Water is one of the most difficult things to animate and render realistically, and making an underwater environment look good isn't any easier. Going off the Manaan FP, the underwater areas that the game engine can pull off are actually pretty basic. It's essentially just a really dark area with some bubbles and seaweed visible, with the occasional Firaxa shark swimming past. It worked in pulling off the creepy vibe needed for the FP (and the original KOTOR, for that matter), but it doesn't hold too much interest for me as a stronghold.
So these are my best ideas. What are yours?