Rate my Pokemon White team!

Hi everyone!
To make this thread short and get directly to the topic, my Pokemon White is coming through the mail and I'm already thinking everyday about my permanent team, it's frustrating and exciting at the same time because I can't wait and there are more than 6 pokemon that I really like. 
I already have a cousin who has Pokemon Black and I'm getting most pokemon at level 1 that are newly hatched and at the desired natures, so please you don't have to worry about which pokemon is found later in the game.
Here's what I kinda think that my team should be, please, feel free to throw suggestions.

-Snivy/Serperior as my starter.
Nature: Modest
Ability: Contrary
-Leaf Storm
-Hidden Power(Rock)
-Giga Drain
-Toxic

-Haxorus
Nature: Jolly
-Outrage
-Earthquake (goes well with his ability)
-Dragon Dance
-Brick Break

-Volcarona
Nature: Timid
-Quiver Dance
-Bug buzz
-Flame Thrower
-Overheat

-Mienshao
Nature: Adamant
Ability: Recover
-U-Turn
-High Jump Kick
-Swords Dance
-Stone Edge

-Samurott
Nature: Naive
-Aqua Jet
-Mega Horn
-Surf
-Ice Beam

Braviary
Nature: Jolly
Ability: Sheer Force w/Life Orb?
-Rock Slide
-Shadow Claw
-Brave Bird
-Fly
(People suggest training Braviary's Attack EVs, but doesn't it need defense and sp defense as well to keep itself alive?)

I really have no idea about items so I'll leave that to you to help me with.
Also one thing I don't understand is, while doing my research, people always suggest that you should train a pokemon EVs in a stat that it higher that the others, so let's say Attack for Braviary. Shouldn't I train the defense and Sp Defense of these pokemon as well, so they can protect themselves?
Thanks for your help!

Requility said:

Your team looks good so far for ingame! Few little things though, Snivy has Leaf Storm twice, what was meant to be there instead? On Volcarona, Fiery Dance is harder to get but can be awesome with QD, so you could replace Overheat because that'll reduce your stats. ;( So ya go for something like HP
rock to hit flying types over Flamethrower, but only if you want !

Uhh also go for a normal STAB on Braviary - Return or something because ingame the others aren't overly needed for ingame. Looks good otherwise though!!

As for EVing you want to excel in what you're best at, and some stats are too bad to fix. It all depends on the Pokemon tbh :( Just switch to a bulkier Pokemon because you want it to do what it's meant to and some are meant to be strong attackers and you want them as best as they can be.

Click to expand...

Woops, sorry about Snivy, it was ment to be a GigaDrain instead of one Leaf Storm.
Also about Volcarona, yes, Firey Dance looks good and I'll learn that, but can I keep my Volcarona with Heat Wave instead of Fiery Dance until it learns it?
The thing is that I'm really obsessed and I don't understand when people at times would keep only an attack of the type of the pokemon, that's why I was aiming at at least two.
I want to battle wirelessly with friends as well, that's why I am considering my team carefully. I put Shadow Claw on Braviary because I have no advantage against Ghost types...
Thanks a lot!

Requility said:

Okay firstly about the attack thing, it's kinda about coverage. You want to be able to use your STABs, but also cover your potential weaknesses too.

An example would be...

Magmortar.

Fire Blast, for STAB.
Focus Blast, to hit things Fire Blast can't otherwise hit, such as Heatran, for example.
Thunderbolt to hit water types.
Hidden Power Ice, or Hidden Power Grass to hit water/ground types, or to hit dragon types.

(Not sure if this is the basic set now buuuut when I used it, it pretty much was, and it's just an example anyway!)

So really, you couldn't afford to have other things on there. You want to limit your switching and therefore play to your best, so you go for coverage over PP. Generally in wifi battles you won't run out of PP easily unless they're status based ore are the 5 PP ones. In in-game you're more tempted to go for PP but even still, it's pretty rare that you run out of PP and only usually happens around the E4.

But yeah to answer your other question, yeah, Heat Wave will be fine, and maybe consider Return > Fly when playing wirelessly. n_n

Click to expand...

I see what you're trying to say and I understand you, maybe it's because I'm a freak and always feared that if my opponed had Disable and would use it on my only attack that is the same as the pokemon type (Flamethrower for Volcarona for example), I would remain without a fire attack to beat my friend's grass type pokemon (just an example).
About the PP yeah, the 5PP attacks are the ones that worry me the most, I'll try to obtain and save as many PP ups.
Thanks for the rest though, really helpful.