Making a good UI is necessary for a full 3D tactical combat. In an RTS game or, for example, a Total War game, you usually command your units to some strategic locations depending on what you want to achieve. However, since space is quite empty, there are no fixed reference points like most RTS games have, and it may be cumbersome and hard to order units to some specific location in an empty 3D volume. The only reason to move your ships there would be because that location is somehow meaningful related to the enemy ships’ locations, and I think that is an essential observation when creating easier-to-use UI for this kind of game. But I’ll jump off that bridge when I get to it.
In the video, I’m showing drag selection of ships. Like many other things, that is quite different to do in 3D than in 2D. You can also see some testing of UI markers like selection boxes and health bars on ships.