Things that patches/mods could enable easily :
Make the game moddable
Ability to turn off chromatic aberration
Loot all faster method
Auto compare inventory weapons/armor to those equipped
Better map! At least more hover info - like the green quest marker, shows no info in the map
Default sleep time to the min 6 hours seeing as that heals you fully
Rebind buttons that are hardcoded (why?)
First planet: remove the silly giant planet from the sky, and the band of rings
Third person mode
Some balance suggestions :
Less loot overall
Nerf melee weapons a bit
Things that are difficult to add/mod :
Cover mechanic (would be really helpful)
Give town NPCs less bland things to say