To me KD making this happen depends on how well Joe Harris plays and how KD/ball movement can create open looks for him. (Again assuming Harden and Kyrie is out. If either one is back they should be good)
The thing people overlook in the 2015 finals was the fall off of JR Smith. Warriors absolutely smothered him. And then he missed so many open 3s when they were (31% 29% from 3, 11 pts a game) If JR played to the level he did the rest of the playoffs they might stole that series.
JR was capable of being a 15 to 18 pt guy that year when needed but it never happened in the finals. Nets system should create looks for Harris. He's capable of a big scoring thats needed.