​When my battle fleet stands in defense of an unoccupied system, this does not prevent an unarmed AI colonizer from flying into the system and establishing an outpost there, occupying the most convenient (often the only) colonizable planet. There is only a short period of time, just a few seconds after the colonizer arrives, in which I can attack and drive him away. Otherwise, I must then maintain the blockade of the outpost and until its completion I cannot colonize the system with my arriving colonizer. This arcade element significantly spoils the pleasure of a turn-based strategy game.

I believe that such "sneak colonization" in the presence of an unfriendly fleet is unacceptable and should be prohibited. For example, it was impossible in Master of Orion 2, which to this day is a brilliant example of turn-based space strategy.

Compare the colonization mechanic to the outpost supplying mechanic: supply ships can't penetrate an unfriendly blockading fleet and reach the outpost. So why would a colony ship penetrate an unfriendly system-guarding fleet and establish the outpost at the first place?

Delivering equipment for colonization to the planet, deploying it and starting the colonization process should be more difficult to hide from an unfriendly fleet patrolling the system than just delivering supplies to the outpost. Therefore, I am confident that colonization of a guarded system should be impossible without the participation of a battle fleet capable of destroying or driving away the unfriendly guarding fleet.