In regards to Citizen Kane, with the critical analysis question being "Discuss the idea(s) developed by the director(s) regarding the significance of an individual’s perspective"

and my answer being

"In Citizen Kane, Orson Welles develops the idea that a person’s perspective about what is most important in life may be affected by their history. Charles Foster Kane’s character demonstrates compensation in the present for pains of the past in such a way he sets himself up for his own demise."

What are three good sturdy topics I can use to write about in my 3 paragraphs?

It has been a long time since I saw Citizen Kane, but to support your thesis, if Wells believed that, then he should have reflected on individual history glimpses to explain Kane's attitudes and behaviours. I would look for examples of that.

This site should help you with an analysis of Kane's character.

http://www.sparknotes.com/film/citizenkane/canalysis.html

To develop your discussion on the significance of an individual's perspective in Citizen Kane, you can focus on the following three sturdy topics:

1. The Influence of Childhood Trauma: Analyze how the traumatic experiences of Charles Foster Kane's childhood shape his perspective and goals later in life. Explore how the loss of his parents and being separated from his childhood home contribute to his desire for power and control.

2. The Role of Relationships and Love: Examine the impact of Kane's relationships on his perspective and personal fulfillment. Discuss his failed marriages and the role they play in his search for validation and happiness. Analyze how his perspective on love and relationships evolves throughout the film.

3. The Paradox of Success and Isolation: Investigate Kane's rise to power and its consequences on his perspective and happiness. Explore how his material success isolates him from genuine human connections, leading to a distorted view of the world. Discuss scenes that highlight his isolation, such as the rosebud sled or the iconic "clapping hands" montage.

Remember to support each topic with evidence from the film, such as specific scenes, dialogues, or visual symbolism. Providing analysis and explanations for your arguments will make your paragraphs solid and persuasive.