He mentions at some point in the game about battling with his 'real' team, I don't think it was worded like that but it was implied he still had his original team from Black and White. Given that he's a new leader, it makes sense that he'd start off as the first gym. And frankly I found him difficult. His freaking Lillipup u_u
I really liked the leaders, though. Roxie had a really cool personality, she was very level-headed. And Marlon's just... Marlon, lol.
I loved the gym redesigns too. Detested Clay's, that was so annoying, but gyms that stick out that I particularly enjoyed were Roxie's, Burgh's, Elesa's, Drayden's, and Marlon's.