I noticed that when you take a system by force you don't get any penalties.

In most 4X you get a period of lowered productivity and unhappiness but this isn't the case in ES2 (maybe just not implemented yet).

The systems should get at least a lowered happiness for a few turns after conquest.

Also unhappy system should do "protest votes" (meaning they will vote for the party opposing the one you supported in the last elections)

For instance they would vote pacifist if you are engaged in conflicts or ecologist if you are trying to get your industry working

Pejman wrote:

I noticed that when you take a system by force you don't get any penalties.

In most 4X you get a period of lowered productivity and unhappiness but this isn't the case in ES2 (maybe just not implemented yet).

The systems should get at least a lowered happiness for a few turns after conquest.

Also unhappy system should do "protest votes" (meaning they will vote for the party opposing the one you supported in the last elections)

For instance they would vote pacifist if you are engaged in conflicts or ecologist if you are trying to get your industry working

The Devs promised a better ownership system. I believe the conquered planet population should not have citizenship and consequently vote rights until there is a high rate of ownership.

Protest votes could be an outcome of rebelling planets with a high ownership.