a forth option may be to have construct robots placing assembly machines before inserters.
however, just now having the foreknowledge of this will be of benefit. Always learn something new : )

game started 5.10
probably a duplicate, but just in case
When placing blueprinted setup with inserters, they occasionally get placed before assembly machine and the belt next to them holding, in my case, copper/iron bars, the inserter will grab the first one it thinks it wants(probably from the far ...

Sorry, I was going to do this cleanup yesterday, but RL got in the way: I cleaned this up so It doesn't look so blah.

just a thought - if you were trying to do 3 or 7 even split, you could probably spin the "oddball" line back around to resupply.

I saw somewhere people were having a hard time getting splitters to split evenly, so I will post this picture. The one mistake I've done and seen is when trying to split a belt that the multiple splitters were connected to each other. If the goal is to evenly split, this is a simplistic design that ...