Answer:
On a deserted island, I would miss : my best friend, some mode of entertainment, the places i used to chill at near my home (residence).
Explanation:
Spending time at deserted places can cause contrasting mixed feelings, of self solitude with missing up.
If I were on a deserted island, I would miss my best friend the most. I would wish that she could be with me & we could spend quality time. Materially, I would miss my laptop & internet, so that there is some source of external entertainment, specially music. Place missed by me would be the places near my home, where I used to chill earlier.