The stick worked for me...but only in terms of up/down/left.right. Fire was annoyingly not on the stick, but the Spacebar, and also the throttle slider didn't work for engines.
What is needed is a key-binding / joystick setup option, so you can configure how the game is played. Essential!
On the graphics front, the polygon count is REALLY going to hold things back. Look at games like 'X2 the Threat' for an idea of where the current commercial games market is expecting. Then, look at the FS Open standard. I know the plan is for lots of ships in a battle, but realistically, how many cap-ships are ever going to be in a single mission?
Taking the flight-sim world for comparison ( coz I know it better ) ...
There is an inevitable trade off between detailed planes and lots of planes. Careful control of levels of detail helps a lot here, with higher detail models for up close. You have to reach a balance, but there should be a point at which you can get high FPS and good enough detail. The trade off may be smaller battles.
Might end up raising the minimum spec for the PC requried to play...
Either way, you need to get this thing looking better to attract buyers, and make the mod possibility more enticing for those who might want to buy a 'sandbox' game.
p.s. ....PLEASE.... correct the text on the website! If you want, I will happily edit that for you

Commercial products need a commercially polished presentation.