Thesis: The theme of guilt is grounded on the general conflict between Victor’s ambition and the restraints of the human society; his pursuit for higher intellect can specifically be a rebellion against these moral obligations.
DUSSINGER, JOHN A. “KINSHIP AND GUILT IN MARY SHELLEY’S
‘FRANKENSTEIN.’” Studies in the Novel, vol. 8, no. 1, 1976, pp. 38–55. JSTOR, JSTOR,
Shelley, Mary Wollstonecraft. Frankenstein. Dover Publications, Inc., 1994.
Your organization of the paper will be especially important in your argument regarding Victor’s rebellion. Getting to the root of Victor’s guilt will require you to pick specific scenes (or one specific turning point) and analyze them/it from the two angles you mention (ambition vs. society).