recently I have became very disappointed with cirucits and when reading the forum I feel that I am not the only one. I wanted to create something useful with circuits and achieve better control of what my factory is doing. The goal was to increase automation and better utilize my assemblers, belts, robots, trains and furnaces.
The problem with factorio is that there are many things where you can not control the things precisely due to the somewhat lame game mechanics. It is very hard and sometimes impossible to control item flow down to a single item. One can barely control which path a single item takes in a splitter.
Some things can be worked around but is means days or weeks of hard work and dozens of combinators. But this is a game and I'd prefer it to be more of a fun challenge. Don't get me wrong, Factorio is a great game, but at a certain point one has built everything and the challenge is gone - except for building complex circuits and smart factories or ever bigger factories.
I really hope a developer reads this. I wish you had a rule to check every change to the game mechanics to determine if it adds that sort of randomness (and breaks the ability to precisely control item flow) before implementing it. Like the inserter stack size change that is heavily frowned upon for the reason that it breaks control of item flow where it was possible before.
Now that I have complained, I have seen that there's already a good discussion about some points in this thread: viewtopic.php?f=9&t=30853&start=100 .
Recently the poll descriptions there changed to indicate that some things have been implemented. It seems like we'll be getting the ability to read train contents. That's good news
Based upon the direction the thread is taking I want to add an explanation for why I feel this is important: When one first discovers circuits they make a big promise. They promise that you can do almost anything and realize your wildest factory automation dream. Then when one takes that promise and tries to do stuff, the game mechanics slap you in your face. That broken promise seems to be a painful moment for many. After that people turn to the forum and make suggestions to improve the situation. The reaction then is even more painful. People say "write a mod" or dev's say "not going to happen". You earn even more slaps in your face