[Tomgs]

One change you can make to this is to edit the AI_politics.txt file to make surrender and giving tribute harder. But I do think that most cultures would surrender if it was the only option other than complete destruction. There could however be exceptions extremely zenophobic races perhaps would never surrender and prefer to "fight to the Last man".

Taqwus I always play as a bloodthirsty race and I don't have a lot of problems maintaining happiness. You just have to build a lot of ships in most systems to boost your happiness. I also build Urban Pacification Centers in all my systems as soon as possible. The Last time I had a planet riot on me was before the first patch. Since then I rarely get planets even getting unhappy. The secret is to declare war early never make treaties with the AI and build ships on planets that are getting unhappy. If you do that you shouldn't see many riots.