Is it intended to be able to build 4 starbases at a star?
The ability to build 4 starbases is quite fun. I play as tec and you can make the 4 bases clumped together for overlapping coverage. Then upgrad them with both trade port nodes and some defensive and fighter hangers. You end up with something that is impossible to attack without torpedo cruisers and/or a super massive fleet of carriers. And the plus side is the money you earn is ungodly if you have a decent length trade route somewhere else. I had a 13 planet trade route and that one star alone was producing about 30 credits/s. Give them lots of HP with defensive upgrades and 14*4 fighter 56 fighters in that one gravity well. It would take 28 carriers just to even the score.
I can't imagine what kind of trouble 4 Vasari roaming starbases could get into if in one star's gravity well.