They would have struggled a lot less if they had thrown out less.

The writers took out a lot, but they seemed to disregard the difficulty of writing plot to replace what they cut.

Dondarrion being just an extra sword is a result of the writers cutting the end of his story and then having to come up with more for him to do.

Maybe if they had let him die bringing back Stoneheart, we wouldn't have had to suffer through the "seven dudes try to capture a zombie for some reason" plot line. Beric would be dead, Thoros and Gendry would be with the Brotherhood under Stoneheart.