Answer: Sentimental.
Explanation:
Sentimentality refers to the state of having emotional feelings towards a subject brought upon by memories of past events especially of happy ones and in relation to other people.
As Jeremiah looked through the yearbook pictures, he felt a sense of nostalgia from the fun and hard-work that he had there and this led him to feel sentimental about his high school days.
Yes, I think that Joyce does have the ability to beautifully describe scenery because of her use of vibrant adjectives and colorful scenery. Joyce is able to capture the beauty Gabriel is seeing with her wording and tone.
Immense can be defined as very large, huge or gigantic. You could probbaly use any synonym of "big" to define it.
~Hope I could help! Stay Safe!~