I was thinking about connecting belts to circuit network.
Belt scanner is a kind of belt in 3 versions (normal/fast/express) that outputs true (signal) when it detects object passing through it
2nd idea is flow controller that outputs average count of items passing through it. Its also a variant of ...

What about faking click event when you get mouse over event when dragging (holding button down)? It should make filling cells below mouse easier.

What?
When setting inventory filters you have to set each cell separately or copy filter that you set before. When you want to set same filter for train it starts to be problematic.

Why?
click and drag when pasting filter to paste same filter into multiple cells (rectangle selection or every cell ...

Actually research progress is displayed only by progress bar. I miss some more detailed info like how many cycles left to research technology. What you think 'bout adding progress bar with label
[---------@@@] (10/230)
in technology menu? It should fit in there without problems and wouldn't ...