Well to me the intent of Obito was to in fact be a warning to naruto in some ways along the same lines as Gaara.
Gaara was his warning of the dangers of lonliness and the devil within so to speak, where Naruto could have ended up if he didnt find his friends.
Obito was the danger of losing his friends and the woman he loved. the nihlistic monster who didnt care about anything except his own happiness and was willignt o destroy everyone elses for it.
Sasuke was his warning about falling to vengance and how that dark road leads to nothingness. How even when you achieve vengance all thats left is ash.
Rin was his catalyst to his fall to the darkness, when she died and seemingly by kakashi his best friend who promised to protect hers hand. He lost all reason to live and instead of survivng the grief he gave into it and let the grief and rage rule him. I dont care ill make a world where your not dead.
How far would Naruto go to bring Sakura back? what damage would he do, who would he kill?
from a story standpoint tobi being obito makes sense, he is playing the clown to distract from his true goals and the role hes taken on as Madara.
So you stick to the basic motives attributed to him
Break the ninja system that cost him his love and life
Reform the world in his image a world where Rin is alive.
By proxy make eveyrone else happy as they live a wonderful dream as well.
No sacrafice is too great to achieve these goals all must burn if needed.
Naruto angers and scares him the most becase he sees himself so clearly in Naruto. he sees the wide eyed optimist he used to be with the naive dream of being hokage and making the world a better place.
At one point he would actively threaten sakura putting her life in mortal danger to show naruto the futility of love only for Naruto to save her at the last moment. Still the close call would have Obito see the lvoe they have for each other and it would cause him great pain and some self reflection as to whether hes doing the right thing.
Eventually naruto breaks through the shell which is aided by when madara reveals or is revealed to be behind all his problems, ie rins death, etc