90* elbows in the flow path cut max flow by 10 to 15%...
"line loss" happens too, as mentioned above... a shorter path is preferred for max flow.
my tire seating chuck clips onto a shrader valve, and has no core in it... once the core is out of the valve stem, there is minimal restriction.

removing any quick connectors from the line helps too... one at the tank utlet is all you really want., or it can also be deleted from a dedicated bead seater line, as on most tire machines... just a hose clamp on a hose, on a barbed fitting...