I actually really enjoyed XIII tbh. People hated the linear aspect of it but I didn't mind that, it enabled the game to stay focused and on point. Story was quite good as well. Especially when you reach a certain point in the game where it opens up and gives you a tonne more freedom.
The thing that most stuck out for me was the combat (paradigm) which was really unique and flowed well. Was tactical and fun. And the music was usual god tier, especially the last boss theme battle. XIII-2 was interesting too with Pokemon/Ni No Kuni esc gameplay, totally skipped the last one for some reason though.