So the AI can expand more?
I'm assuming that by expand more, you're referring to the AI colonizing. I tackled the same issue about a month ago. My solution was to do away with the Administration cost for colony ships altogether. I did it this way instead of just giving everyone more administrators, because the AI could simply use those extra administrators to build more constructors, or really for anything else for that matter. This way it only affected their ability to colonize more.
In the ShipComponentDefs.xml file, look for the colony module and the Torian colony module. "Make a copy of the file first and add the newly copied file to the Game folder of a new mod. Never alter the actual game files.
<ShipComponent>
<InternalName>ColonyModule</InternalName>
<DisplayName>ColonyModule_Name</DisplayName>
<Description>ColonyModule_Dec</Description>
<ArtDefine>Colony_01</ArtDefine>
<Category>Modules</Category>
<Type>ColonyModule</Type>
<PlacementType>Module</PlacementType>
<Stats>
<EffectType>Value</EffectType>
<Target>
<TargetType>Ship</TargetType>
</Target>
<BonusType>Flat</BonusType>
<Value>10</Value>
</Stats>
<Stats>
<EffectType>ManufacturingCost</EffectType>
<Scope>Queue</Scope>
<Target>
<TargetType>Ship</TargetType>
</Target>
<BonusType>Flat</BonusType>
<Value>8</Value>
</Stats>
<Stats>
<EffectType>SupportMass</EffectType>
<Target>
<TargetType>Ship</TargetType>
</Target>
<BonusType>Flat</BonusType>
<ValueType>Special</ValueType>
<SpecialValue>
<Special>HullMassScaleMod</Special>
<ValueParam>45</ValueParam>
<ValueParam>0.05</ValueParam>
</SpecialValue>
</Stats>
<Stats>
<EffectType>CanColonize</EffectType>
<Target>
<TargetType>Ship</TargetType>
</Target>
<BonusType>Flat</BonusType>
<Value>1</Value>
</Stats>
<Stats>
<EffectType>PopulationCap</EffectType>
<Target>
<TargetType>Ship</TargetType>
</Target>
<BonusType>Flat</BonusType>
<Value>3</Value>
</Stats>
<Stats>
<EffectType>Maintenance</EffectType>
<Target>
<TargetType>Ship</TargetType>
</Target>
<BonusType>OneTime</BonusType>
<Value>23</Value>
</Stats>
<Stats>
<EffectType>AdministrationUsage</EffectType>
<Target>
<TargetType>Ship</TargetType>
</Target>
<BonusType>OneTime</BonusType>
<Value>1</Value>
</Stats>
<Prerequ>
<Techs>
<Option>ColonizationTech</Option>
</Techs>
</Prerequ>
</ShipComponent>
__________________________________________________________________________
This part here, is what you will want to delete.
<Stats>
<EffectType>AdministrationUsage</EffectType>
<Target>
<TargetType>Ship</TargetType>
</Target>
<BonusType>OneTime</BonusType>
<Value>1</Value>
</Stats>