Option to choose Race aligment during custom race creation. At least a bit.
Option to disable constant Greetengs/The most civs=>Research=>Capital after loading.
Planetary Defence Stations, built by Constructors. Provide minor or passive defence against invasion. Just prevent transports to invade until stations are destroyed.
Options for zero class planets: Make some 0-class planets different, like Gas Giants, Toxic Enviroment, Wasteland and others
Constructor's improvements for different types, at first there can be built some structure like Work Station around or on that zeroclass planet and then it can be improved with this:
-Rare Chemicals Mine(Gas Warfare Cheaper or removed "decrease quality" factor + some bonus, available to build after some tech researched);
-Tourism base, ancient ruins(Like City in the Sky for Gas Giants and Valley of the Kings for Wasteland);
-Asteroid thrusters' facility(Transport asteroids for refining so +to social production and Mass drivers' suage cheaper)
-Hidden Research Facility - bonus to research at random branch of res.tree(can be discovered only with Sourvey module or Sensors II, otherwise marked as useless planet - they still should present, not everything can be put to use)
-Empire's Junkyard(only one allowed) - provide system-wide/Empire-wide morale and/or pop growth, can be trade good. Possible for wasteland-type zeroclass.
-Rare fuels(+1 speed in sector, Toxic type of zeroclass)
-Reabilitation base(For Good, Gas Giant) - Base wich privide help to people in need. +morale+pop growth in Sector it's built.
-Excavation Sites(Neutral, Wasteland) - Site in wich people observe remains of ancient civilizations and learn about them. +Economy/Trade.
-Labor Camps(Evil, Toxic) - Labor Camps, no more or less, dump all scum ofthe galaxy to dig uranium and refine chamicals. +Mil production+loyality.
-Operational Base(one per system, every type of zeroclass) - provide minor info about system's whereabouts(like minor spy level)
Upgrades. Not like I then II then... but I or II or...
==Upgrade I - Monitoring stations: Provide medium info(no further or spying would be useless)
==Upgrade II - Sector Command:Privide Info about sector i.e. reveal fog of war for entire sector it's build. Req ==Scanners II.
==Upgrade III - Patrolling Command: Add attack/def to our and allied freighters.
Suggestion for Eden device - it can be just improvement like ED stage I etc. until some stage is reached with some techs allowing to drive that improvements further. Example:
Early tech: 5 constructor ships required to reach final stage, allowed for the time beings. Can press something like "Initiate Terraforming" and get class 3-4 planet.
Mid-Tech: We know some Xeno farming and soil blah blah blah, can add some techs that make some logic and can now we can add up to 7-8 conships and get planet 7-8 as a result. Same with late-tech. Surely there must be "She's gonna blow!!!" option, representing chance of failure of planetforming - additional planed is a HUGE advantage to make it easy-gained so process should be expensive at later stages where planets of 5-9 class are expected. As well as option for autocolony for newly created planets.