>>35699374Adding to this, Gym Leaders now have at least a little bit of story involvement like Gen V.
Clemont could be fought the first time you're in Lumiose in a double battle with Bonnie (focusing on Pokémon with Plus and Minus), mostly because you just got a second starter and it makes sense to encourage you to have them battle together right away.
The Gym order would then be Viola, Clemont and Bonnie together, Valerie, Olympia, Wulfric, Ramos, Korrina, Grant - as mentioned, one or two could be replaced for the sake of changing things up from XY.