Sounds like a fantastic project, can't wait to see some more details.
From the designs you have posted it looks like fuel logistics will become a very significant part of the game and also part of ship and engine design. I guess once play tested a bit you can tweak fuel consumption / efficiency to see balance proportion of ships that will be taken up with fuel stores and also mining and fuel production rates.
I guess boarding actions are going to pretty much going to become a thing of the past.
I agree that combat is going to need a re-work. Perhaps ships will need a manoeuvre rating as well as acceleration rating to indicate how well they can adjust course quickly to avoid fire - this could be adjusted on ships by the use of thrusters as an additional component to engines. Chance to hit then become related to this factor as much as base speed.
For weapon systems I can see energy weapons needing quite a change as well. Perhaps you have two weapon ratings - one to deal with engagement speed ie the actual speed of the hostile and another to deal with the manoeuvrability of the hostile as above. Otherwise people will need to have very significant turret tracking to deal with heavy burn ships.
Of course Steve if you need any help play testing any of your changes happy to help!....
Fuel logistics will definitely be a huge part of the game. A lot more fuel will be consumed so I think I might radically improve the extraction rate of Sorium from gas giants.
I have been loooking at course changes. The ideal course change mechanic is going to one that is simple to understand yet gives the right feel for the physics involved. For the moment I am working with a one degree course change requiring delta-V equal to 1/90th of your speed. This is very simplistically based on the fact that reversing course and achieveing the same speed requires a delta-V equal to double your speed, so if 180 degrees = 2x speed then 1 degree = 1/90th your speed. So if you are moving at 2000 km/s, a five degree course change will require 5/90 x 2000 km/s = 111.11 km/s of delta-V. If your spacecraft has an acceleration rate of 15 mp/s then the course change would require an engine burn of 123 minutes. I may make this more simple and use 1% of velocity per degree rather than 1/90th. It is slightly more generous but far easier to visualize for players. In this case, the above would require an engine burn of 111 minutes.
Given the relative difficulty of altering course and the fuel requirements to reach high speeds, I think average speeds may actually be a little lower in Aurora FTL. Therefore it may turn out the existing tracking ratings are actually too high
. I'll see how playtesting goes. Boarding actions may actually become easier too. I will be basing it on speed and course differential so if you can match course and speed, you will be able to board ships that would be moving too fast in normal Aurora.
Steve