I haven't bought this game (even though I've got a PS4 & a PS3 even for GT6) as I read in all reviews that there's very little offline content. I did read recently somewhere that through update patch more offline content will be added a la previous GT versions!
I packed my PS4 & unpacked my PS3 for GT6 as I had bought PS4 for F1 2017 game. I missed GT a lot but wasn't convinced enough to buy GT Sport yet. Hence, I returned to GT6, which PD will support till March.
Luckily, I can be patient enough till more offline content has been added within GT Sport. It surely is such an unusual release by PD for being so compact. Even GT5 prologue looked so much more.