You should clarify that your chart is for Empires only, not for Pirates.
Military ships don't need a branch for every ship, but if you are going to do that, you might as well order them nicely in order of AI size or as ordered under the Empire Summary Screen for clarity.
Also, since the original issue was for State vs Private, perhaps you should also sub divide the State and Private ships. or a small bubble indicatin th private sector ships (freighters, passenger, mining ships, mining stations).
Place the order of the colony and construction ship in the order of the build display.
BTW, what program are you using to create this branch chart?
All good suggestions, I will make those changes, thanks.
I am using the freeware but abandoned Cayra mind mapping software. This is a link to a download site only. The devs gave up on this a few years ago. Its a shame.