I've been thinking this since the first time i've played. I want more control over splitting. The programmable splitter has extensively been named. It's in the game already, Just very hard to obtain.
I would like to see alternate versions of the splitter. Like 1 that has:
This would have a bigger footprint, but I wouldn't have to mess around with belts anymore, the exits are then nicely aligned for going to i.e. an Assembler.
Another one I'd like to see is a version that has 2 exits, one on the same level as the input, and one at the level above, so you can use the stackable conveyor poles for nice alignment with the low belt.
These would give better control over the splitter flows.