ORAS OU My poorly-built Gallade Core team

[tinyranitar]

Heatran @ Leftovers
Ability: Flash Fire
EVs: 248 HP / 192 SpD / 68 Spe
Calm Nature
- Lava Plume
- Toxic
- Taunt
- Stealth Rock

Kyurem-Black @ Life Orb
Ability: Teravolt
EVs: 156 Atk / 100 SpA / 252 Spe
Naive Nature
- Fusion Bolt
- Outrage
- Ice Beam
- Earth Power

Gallade @ Galladite
Ability: Steadfast
EVs: 4 HP / 252 Atk / 252 Spe
Jolly Nature
- Swords Dance
- Close Combat
- Zen Headbutt
- Ice Punch

Serperior @ Life Orb
Ability: Contrary
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
- Leaf Storm
- Dragon Pulse
- Hidden Power [Ground]
- Giga Drain

Chansey @ Eviolite
Ability: Natural Cure
EVs: 248 HP / 252 Def / 8 SpD
Bold Nature
- Soft-Boiled
- Toxic
- Substitute
- Seismic Toss

Bisharp @ Life Orb
Ability: Defiant
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Sucker Punch
- Swords Dance
- Iron Head
- Brick Break

Basically this is my team. I am new to the forum so please help me out a little bit! I have just started playing competitive battle after a long hiatus (probably >1 year).

This team is based around my Mega Gallade. I heard that Bisharp and Gallade compliments each other a lot, so this is what I came up with. I'm open to any suggestion, and it's okay to be harsh. I do quite okay with this team, but there is something lacking, I don't know what is.

 

[IronBullet]

Hi there, welcome to Smogon! Unfortunately I'm going to have to lock this thread as you need to provide in-depth descriptions for each Pokemon to explain your choices and their roles as required by the RMT rules. Please read the rules carefully and take a look at other RMTs and the RMT archive to see the kind of detail and format we require before posting a thread here. PM me with updated descriptions once you review the rules and I'll unlock this.