I have a selectable 4 channel paint mixer blueprint that is packed on a 3x3 platform. I have tried multiple layouts and I can't figure out any other way to do this that will fit. Due to the design, i have a combination of launchers and straight pipes being used to put fluid into tanks, or into mixers and then tanks. It takes a while to initially fill the fluid tanks with the colors. I attached a screenshot that begins to show the certain tanks seem to have a "priority." Specifically, anything that is directly connected to a pipe fills after any launchers fill. Any fluid after a launcher cannot go backwards, so as the fluid has nowhere left to go it fills its tank or paint mixer. But anything with a direct pipe hooked up to it will explicitly not fill up unless no launchers need to be filled. I think based on observation that the priority is Launcher > Mixer > Tank.
Additionally, when testing, I will notice that some of the fluid tanks will drain faster than others. At no point is any pipe bottlenecked, however due to the fill priority, I worry that under load it wont keep up for certain colors on certain channels (even though, on paper, it should).
I do not necessarily think this is a bug, hence why it is feedback and not a bug report.
What I do think is that either:
A) All things connected to pipes should have equal fill priority. This immediately solves the problem, but I imagine it would introduce issues that the fill priority was preventing. Leading to...
B) All things connected to pipes should have a configurable fill priority. This is more complicated but both solves the problem and any potential problems introduced by a blanket flat fill priority suggested by A. Or...
C) Add a 1x1 One-Way Valve. This is effectively what the launcher is doing for any fluid tank behind one directly. If it has equal priority to the Launcher, then it can be inserted anywhere you need similar functionality easily.