I'm gonna start by saying if an Anime has any form of criminal/mafia type story, I'm usually a sucker for it - and Great Pretender was no exception. The story, contrast to what others reviewed - I believed to be very good! The overall story, sure, is simple but was executed amazingly!
Stories with great characters will always be more appealing to me as I feel good characters are the main aspect towards me liking or disliking a show. Great Pretender has an amazing ability to make you feel a connection to each character and goes into all of the main cast's stories for each arc. Each character was very likable and their stories added a lot of depth to each of them which I liked very much! My favourite character - like many, was Laurent. He was such a likeable asshole and he truly added a lot of amusement to the overall story. I knew every thing that came out of his mouth would be amusing, a really cool character!
If you're an idiot like me, there will be certain points within the first arc you might genuinely not see coming - after the first arc everything becomes predictable - not in a boring way, though. All of the cons the characters play out are still very amusing and you are sometimes left with a "wait... how are they gonna pull that off?", it usually is pulled off in very dramatic and silly ways, but it just adds to the overall fun of the series and is very enjoyable to see how they pull off a con in each arc.
I very much hope to see another season of this show eventually but was also very happy with the ending as well, if they chose to never add another season I will still be left satisfied.
I also feel it would be wrong for me not to bring up the beautiful aesthetics of the show! The backgrounds and shading were always so pleasing to look at and each second showcased beautiful artwork! Loved it!
TL DR; A very fun and beautiful show with great capabilities to make you feel attatched to each character they introduce, even some of the side characters are made to be very likable. Lots of amusing moments and fun/entertaining till the very end! Hope to see another season but was left satisfied regardless. I rate a 10!