Advice on a PS4-related gift for a 15 year old boy?

hi!

i'm very out of the loop when it comes to PS4 related stuff, and was hoping some peeps here could help.

my younger brother has a PS4 and a birthday coming up, and i'm trying to think of a gift for him. he's good on accessories, so i'm thinking he'd like a new game.

games he's really liked in the past are terraria, kingdom hearts, ratchet and clank, and osu.

my research has shown that some good options are either that new crash game, rocket league (his internet isn't that great, bad idea?), or the latest final fantasy. is there anything else you all would suggest over these, or one in particular out of the three?

also, any issues with used games on a PS4? he'd probably be happy or happier with a stack of interesting used games over a new one. trying to keep it $50 or under.