question: AI colony and trade ships

By mid-late game every AI seems to have many colony and trade ships sitting idle.  Idle colony ships bug me the most, it uses up valuable admin points and I can see planets within their range to colonize but they just sit idle.  Trade ships continue to be built despite the ai having no more trade licenses.  Just wondering if there is a way to do a mod to fix or minimize this and what files i should look at