I am playing Pokemon Black, and I am having trouble deciding on a team...

I would recommend you get rid of Vanilluxe.

After you do that, I would recommend you add Scraggy and Tynamo. I would also recommend you evolve these two Pokemon until they're in their final forms.

Hope this helps!

Maybe Escavalier, Volcarona, or Darmanitan. You could also do well with a dragon (Haxorus or Druddigon), or a fighing (Meinshao, Throh, or Sawk).

I would recommend getting rid of Simipour, Musharna, and Eelektross if you want this team to go anywhere competitively. If you want a special attacker, I'd replace Musharna with Chandlure, as he can counter the Ice types that Flygon and Serperior are weak to, and can absorb the Fire moves that Serperior and Mamswine are weak to, without even taking damage.

Instead of Eelektross, I would suggest Galvantula, as Eelektross is just too slow, and doesn't have as much coverage. Galvantula can also be used to lure your opponent into using Fire moves to boost Chandlure. But Galvantula's biggest advantage is his ability, which boosts Thunder's Accuracy to 91, instead of the usual 70.

If you're looking for a Water type to use, I would suggest Swampert, Gastrodon, or Gyarados instead of Simipour. Gyarados is a physical sweeper, which you already have in Flygon and Mamoswine, so you should probably go with either Swampert or Gastrodon. Gastrodon makes a pretty solid wall, and can absorb any Water moves directed at Chandlure with his Storm Drain ability. His weakness to Grass moves can similarly be dealt with by Chandlure or Galvantula. Gastrodon can force switches with Yawn, induce poison with Toxic, heal himself with Recover, or he can use Scald to deal damage and possibly Burn your opponent. Swampert on the other hand, can set up entry hazards with Stealth Rock, induce poison, or set up with Curse and then RestTalk his way through your opponent's team.

So there's my suggestions. Hope they help you in some way.