Option for nuke planet changes depending if there is your race on the world or not. If there is, negative modifier applies, if not, then there is no negative modifer.

Evacuation for Fanatic purifiers and xenophopbes only evacuates (removes) people of your race (and robots).

Check there is a free tile when adding tile blockers so world is not accidentally uncolonizable.

Ignore colony: Have your administration ignore the colony in question denying it resources and attention and severly stunting its growth while you continue to collect the resources from it. This action adminastritivly removes the colony from your total planet limit and you do not send resources to that world any longer essentially squeezing it dry. However the AI will in response cause the colony to act autonomosly to a very small degree building buildings that will aid in developing its self sufficency. During this time unrest will steadily grow and once reaching a certian point the colony may try and succeed from your empire.

Lazifare: In short your empire turns a complete blind eye to the goings on down on this planet essentially ignoring what transpires down there. It will develop on its own and while still within your empire will not impact your planet limit and will gain a small bonus to resource production. However over time effects can hit the world like burst economic bubble (leading to it tempoarily hurting your economy) to even independence movements and demands for further autonomy.

Sanction: You essentially block off a specific resource from a world and are unable to build or move pops on this world, but can still gain resources at a reduced rate and it will encorage people to move. Its main benefit is that for the first 5 years it will drastically lower unrest levels and ethinc divergence but after the 5 years are up it will gain a huge bonus to unrest and ethnic divergence and can lead to demands for sucession, riots and even the whole colony and narby sisters succeeding.

Abandon: In short you can abandon the colony essentially making the world a pre space flight culture in either the machine or nuclear age that will rapidly develop towards space flight. They will be understandibly cross that you left them to die on that world.

One thing that i woud like too is, expanding this to get rid of unwanted habitats. that you can evacuate them and destroy the habitat in the process.
Other thing is, a way to abandon colonys that are allready a bit bigger, but with a bigger penalty, cause in my current game, i cant abandon any colony cause i dont manage to lower the pop down to 2.

Agree with and second all the current suggestions to make it possible to abandon colonies with more than 2 pops, to abandon habitats, and to make it possible to abandon colonies as a hive mind.

I guess this is only for me alone but I created a galaxy where humans are the only dominate species in the galaxy and the nations of the world has been divided into different empires. For example, Russia is basically called the Union of Soviet Star Republic and the United States are called the United Sectors of America.

My idea is for one of my other nations called the Japanese Directorate (which is a science directorate btw) where the empire could identify the planet as being corrupted with a incurable virus which the empire can evacutate as many healthy civilians as possible while leaving the sick to die from the virus. To me, that would be cool knowing that one of your planets has been infected with a virus that is incurable. Just a suggestion of course.