4 refienry hubs (so do
Nice.
In my case, I have 4 hubs. Yet still 0.5 colony, 0.5 refinery. You can see the difference here (maybe from extra dev. points from buildings around the system):
That is really interesting. Mine is also a .5 split. Perhaps additional hubs have no effect on market influence.
I'm probably going to start developing in this system again so I'll share updates on the market if Dev increases also increase my market size.