As for right now, change Buizel, right now. Buizel is a terrible Pokemon. You can use a Grass Type instead. Good options include Cherrim (Petal Dance destroys the early game) which is found at the rooftop of the Chrysolia Hotel. You can use Leavanny, too, which evolves REALLY early, since you can just run around to increase it's happiness, it's found after beating Challenger Mars, i think, at the Goldenleaf Cave (which reopens after you reach Goldenleaf Town). Blitzle is also a terrible Pokemon. Since your team covers pretty well Water (if you use a grass type) and Flying types, there's no need for including a Blitzle, but if you want to use an Electric type, use Charjabug. It's better if you save Nidorino for later, after it gets Poison Jab at level 38, I think, and Earth Power as a Nidoking at level 43. Klink is an amazing choice, although it evolves pretty late, Gear Grind does so much damage, and it will cover Fairy, Ice and Rock types really well. Especially good for the Ice gym, Shift Gear + Gear Grind ruins her whole team. With the team you have right now, Keta will give you A LOT of trouble. You may have Woobat, or even evolve it into Swoobat, but it will need more support. Vivillion is a great choice, since it learns Psybeam for the battle, but I'll explain it's usefulness later on. Lastly, Mightyena, great attack for the early game, and it has Moxie, also, it may be useful against the battle in the Wispy Tower, though I won't spoil that to you.
Well, here comes another large piece of text.
Sylveon: You can find Eevee just after arriving into Sheridan Village, trough the 'Battle me again' quest, but it's better if you complete it after beating the events in Carotos Mountain. Sylveon is an amazing support Pokemon, thanks to it's access to Misty Terain and Wish (if the Eevee has it as an egg move). It hits really hard with Moonblast, and it's really bulky, too.
Ambipom: With Flash support from another Pokemon, this thing destroys Narcissa's gym, but it doesn't stop there! Found in Route 2, Ambipom has the Technician ability, which basically grants it a 60 base power Fake Out, which can follow shortly after with a Double Hit, OHKO'ing almost everything on it's path.
Espeon: Breed another Eevee, and unleash the power of the Psychic cat. No need to explain it. Sky high special attack, amazing speed, good special bulk, learns Psychic moves early.
Talonflame: As soon as it evolves at level 35, it will have access to Flare Blitz and Brave Bird. Acrobatics, learned at level 44 is best tho, since it doesn't harms Gale Wings priority, which makes Talonflame an effective revenge killer (Gen 6 flashbacks). You can get it at Oceana Pier, there's a small portion of grass with a bunch of Fletching on it
Vivillion: Good in the Early game, and amazing once it gets Sleep Powder and Quiver Dance. Since it has Coumpound Eyes, it basically gets Spore, which we know is OP, and a reliable stab move in Hurricane. Vivillion is an amazing support pokemon in doubles and can be an effective sweeper, too.
Those are the things that come to my head at this moment, but feel free to ask me anything if you need advice, or something ^~^