Was just thinking that it would be really cool if the minor nations might engage in piracy, and if they were successful, they would become more powerful fleets and pirates in their gravity wells. As it is they're mere;y a time delay before your take out their systems, and having them be agressive would make them more interesting, and make defending your systems more important in the early game. Having multiple pirate bases in each star system would also be very interesting.
Additionally, having Diplomacy make these nations likely to join you quicker than the typically run out and kill their fleets with my free Capital ship might make Diplomatic techs more appealing at first, which could leave you behind when you start running into major nations (or human players)