This is such a great idea for a mod and I love and I am currently building my new destroyer around them.

a couple of things that I have found that are challenging

the hub (6sided) and even the 5 sided is incredibly hard to move through due to the brace bars. I realize that the tube might look a little flimsy without them but unless you are in zero-g they are impossible to move through.

Having adaptor blocks with a conveyor port on every surface would be useful. so an end would have 5 conveyors and a 5 way would have 1 conveyor would be helpful. I have found I like the tunnels because I can get in them and repair them unlike along a run of conveyor pipe. I realize that some people have seperate networks for different things and might not want that type of connection but it would help in tight spaces.

I wish that there was a good vertical move option for the tunnels like a ladder for gravity wells but I can imagine that its complicated. and too be fair its a problem in general in this game.

Keep up the great work, This mod has drastically change how i build and I appreciate it.