I wanted a firm grasp on the game before posting ideas, so after 150 hours I'll post now.
When creating a ship can we please get an icon for the hud display, right now it's left blank when in a fleet.
AI creating space stations in your territory "without" an open borders treaty, destroying said space station triggers war.
Fix: Only allow players with an open borders treaty to create a space station in your territory, If a players star base is overrun because of influence give a diplomatic option (to both sides) to remove the star base or "sell it to the current owner of the territory," lastly destroying star bases in your territory should not trigger a war, angry yes.
AI's not properly setting up a planet for good/max benefits, and not using economic rings to strengthen themselves. AI's not utilizing capitals properly.
Trade routes: longer = better is lame easy yes, dull you bet ya.
Directing trade routes to planets with positive income should net more no matter the distance, a display for players "trade capitals" should also be available in the trade menu, trading at them "should" net higher income for both parties. Rough suggested formula: ((0+(trade capital 1.25) * (distance /100, if < 0 = 1)) * (planetary income / 50)