Two 4K displays on 2015 MacBook Pro 15" and ordering of Thunderbolt devices
You really don't run into issues with the ordering of devices in Apple chain able hardware. Whether it's FireWire or Thunderbolt, the only rare situation is where you mix generations.

For example a firewire 400 cable should go at the end of the 800 chain. Same for Thunderbolt 1 and 2 (and soon 3).


Can I daisy chain Thunderbolt to FireWire 800 to FireWire 400
Does daisy chaining FireWire 800 and 400 cause all devices to use 400 speeds?


I haven't seen any issues with powered off thunderbolt drives in the middle of a chain to the display, but I'd probably put the display first and then plug the drives in down stream of the display if you have that option.