I gave it couple more hours and it has grown on me. Managed to clear out all contacts in a sector.
There's a lot of very interesting stuff in there. The sector generator is quite nice, it pleasantly surprised me with variety. I love the weapons system. The general feel of controlling something big and heavy through mostly indirect commands.
I'll focus on problems and improvement opportunities though. I'll just throw some notes at you so forgive me if they are a bit disorganized or repeating.
I know the game is meant to be a simulation of sorts, but I'd sacrifice some of the adherence to the simulation paradigm in favor of pure gameplay and monkeybrain feelgood. Realistic simulations are almost always boring, but the idea that you play a simulation is exciting. So my general mantra for simulation games is - never make a simulation, always make an illusion of simulation. Illusion that's more pleasant than the real simulation but still tricks the player into believing they're dealing with a serious simulation. In short, remove/compress all tedious simulation aspects, amplify all pleasant/fun aspects while not breaking the illusion of simulation.
Controlling the ship is hard. Both schemes have serious disadvantages. I'd think about having a single scheme but delegate tedious/confusing parts to auto pilot.
The ship should feel a bit more agile/responsive, regardless of type. Qucker steering. Quicker thruster change, quicker velocity response to it.
Get rid of the notion of horizontality completely. The main goal of controls is to point the ship into wanted direction. For that, you don't really need the whole yaw-pitch-roll system. You can drop the roll altogether. Roll (and notion of horizontality) is important only in atmosphere/gravity bound flight. In space, it doesn't really matter. It's not important how your imaginary wings are rolled relative to some imaginary plane when approaching the target. To point the ship you only need to adjust longitude and latitude, which translates to yaw and pitch. The roll can be just cosmetic. So I'd use only 2 degrees of freedom and map that to WASD. Optional cosmetic roll can go to QE.
Once there is no horizontality, you can drop the rendering of horizontal plane and you don't need Elite style bars in map view to show target distance from that plane.
All targets should be highlighted on hud, in both views, possibly by putting a square marker around them. A target should display distance and optionally the time to reach it in your current and maximal cruising velocity. You can select any target at any time and tell the autopilot to point the ship towards it, keeping your current thruster state. It can keep doing that during dogfights.
Approaching collectables is slow and boring and the reward is often not worth it. How about this instead: Use the above described autopilot to get the collectable into your range. Once in range, send out fast pickup drones to collect it. You can have multiple such drones and assign them to multiple pickups at once, or assign multiple drones to a single pickup to retrieve it faster. Alternative may be tractor beams with similar function.
Projectiles seem kinda slow. Make them faster. They'll be more satisfying to watch. Make the moment of firing a weapon more pronounced via some audiovisual effect so I know when I'm unleashing destruction. Every weapon phase should have some sort of duration/progress indicator. An enemy that's currently targeted by one of your weapon systems should have a corresponding mark visible on hud at all times.
I was very close to ships and I couldn't fire and I didn't know why. All blockages/cloaking should be made known. When an enemy in range is clicked on, display all information categories that you can possibly get about it, but for unavailable categories state the reason they're unavailable.
Destroying enemies is hard. I want rewards. I wiped out a whole sector and got nothing for it. Always reward some instant credits on enemy destruction. On top of that let the destroyed ship always leave several pieces of loot you can collect with earlier described pickup drones.
Enemies are too clustered. In addition to organized hard enemies, put plenty of weaker single ships flying around the sector for player to sadistically prey upon and practice fighting. The rewards should be smaller for them, of course.
I'll stop here for now. Will write some more if I think of any.