1) When I zoom out Id like to be able to view an entire galaxy at once, even on the bgigest map size. I can see perhaps the developers don't like this because then you have far too many icons on screen at once, so I have a suggestion. When you zoom out planet models change to icons. So, what if star systems changed into icons? When your zoomed out and can see 40+ star systems at once I'd rather see a medium sized icon with the name of a star or an icon with smaller race icons listed.
2) The font. Change the 8/6/2 and a few other letters that get easily confused.
3) Ship names of surrendered races. Today the korx surrendered to the altarians and they had a lot of ships. So I have lots of korx fighter #xxxx roaming the galaxy in all the colours fo the rainbow. It just doesn't feel right.
4) Ship selection highlight. When you've got a ship selected the little graphic underneath can be awkward to see sometimes. So if the ship icon itself would glow or pulsate or do something else other than obscure the selection graphic it'd save much time.
5) Influence highlighting. It would be an immense improvement if I had the option to shade in the map where influence is between the borders. Sometimes coloured borders just aren't enough and you have to look for a few seconds to figure it out.
6) The option to play without espionage. Most other 4X turn based games have this, and I've never liked the intelligence type aspects of the games so I always turn it off if I can.
7) Build speed multipliers in game start settings. Sometimes I get frustrated that my big planet full of industrial sectors being fed by my huge cash income is building as slow as it is. Sometimes I want ships to build slow and sometimes I want big fleets of ships attacking each other.
8) Voting for war. Sometimes when I wage war on an empire a ship of an empire with a similar colour is nearby and I go to destroy it and click to wage war without thinking. I realize my mistake when I see the vote dialogue but there's no option to cancel the vote and prevent war leading to disastrous consequences.
9) Disruptor III and subspace blaster components. Disruptor 3 is cheaper, does the same damage, takes up same amount of space yet it comes before the subspace blaster in the tech tree? Is this a typo somewhere that was overlooked?
And a not so small idea:
Objects or obstacles that take up more than one game square. Think gigantic stars, or nebulae that span several parsecs, persistent wormholes, deadly black holes, or show pieces in a map.