Haha, my Hodgepodge team!

[Flames of a Phoenix]

Based on my reading this board, the Pokemon I like, and what I have to offer/put time into.

Rhyperior w/Leftovers/Choice Band
Adamant (252 Atk, 252 Def, 6 HP)
Stone Edge
Brick Break/Hammer Arm
Earthquake
Megahorn

Tanky-sweeper thing.

Darkrai w/Leftovers
Modest (255 Sp. Atk, 255 Def)
Dark Pulse
Thunderbolt/Ice Beam
Calm Mind
Dark Void

Uh, Sp. Atk thing?

Milotic w/Leftovers
Modest (252 Sp. Atk, 252 Sp. Def, 6 HP)
Surf
Ice Beam
Hypnosis
Recover

Wall?

Metagross w/Choice Band
Adamant/Jolly (252 Atk, 252 Spd, 6 HP)
Earthquake
Meteor Mash
Explosion
Zen Headbutt

Atk sweeper?

Dragonite w/Lum Berry
Adamant (252 Atk, 252 Spd, 6 Def)
Outrage
Dragon Dance
Thunderpunch
Stone Edge/Roost/Aerial Ace

Another attacker...

Gallade w/Choice Band
Adamant/Jolly (255 Atk, 255 Spd)
Leaf Blade
Close Combat
X-Scissor
Sword Dance

Another attacker.

My problems is not understanding EVs very well. As in, how many EVs can each stat take and whether to have a Pokemon be fast or when to add EVs to HP. These are mostly Pokemon I like, which is why I included a legendary. Hopefully I didn't overdo the Choice items. This is my first time. All of this is theoretical and not trying to be innovative.

[Near]

Rhynferior:
-Hammer Arm [Only hits Normal types]
+Avalanche

252 HP 252 Attack 4Def. Must.

@Choice Band

Darkrai, as I said before, goes Beam.

255 Def is pretty dumb. 255 Speed.

Milotic wants 252 HP 146 Defense 106 Sp.Attack

Metagross is Adamant.
That set works, but CB has been a ***** to me,
so I switched to Agilligross.

You don't max speed with CBGross.

Dragonite@Choice Band
252 Attack 252 Speed 4HP

Outrage
Waterfall
Earthquake
Thunderpunch

Gallade with CB and Swords Dance.
Right...
Gallade@Choice Scarf +Psycho Cut -Swords

[Flames of a Phoenix]

I meant Spd instead of Def for Darkrai, sorry. Updated with Near's advice.

Rhyperior w/Choice Band
Adamant (252 Atk, 252 HP, 6 Def)
Stone Edge
Avalanche
Earthquake
Megahorn

Darkrai w/Leftovers
Modest (255 Sp. Atk, 255 Spd)
Dark Pulse
Ice Beam
Calm Mind
Dark Void

Milotic w/Leftovers
Modest (252 HP, 146 Def, 106 Sp.Atk)
Surf
Ice Beam
Hypnosis
Recover

Metagross w/Choice Band
Adamant (252 Atk, 146 Spd, 106 HP)
Earthquake
Meteor Mash
Explosion
Zen Headbutt

Dragonite w/Lum Berry
Adamant (252 Atk, 252 Spd, 6 HP)
Outrage
Waterfall
Thunderpunch
Earthquake

Gallade w/Choice Scarf
Adamant (255 Atk, 255 Spd)
Leaf Blade
Close Combat
X-Scissor
Psycho Cutter

Questions: Waterfall is on Dragonite for earth/rock Pokemon with rock moves, right?
I changed Metagross' EV spread to match the numbers of Milotic. Do the numbers generally work out to be 255, 252, 146, 106, or 6?
I looked over my team and didn't notice any glaring weaknesses, would there be a specific Pokemon and/or set that would bring my Pokes to ruin?
I thought about a Hypnosis/Focus Punch for Gallade. Regardless if they switch out, Focus will hit. Has this combo done well?

[Near]

Dragonite is @Choice Band if you go for my set, which should be the best he can do excluding Roost.

Waterfall covers types, so yes.

EVs:
I usually give them how I see it,
but sometimes I consider extra speed and such to outspeed certain Pokemons.

I really see no point for Metagross and speed though with CB.

I'd go Agilligross personally.

Gallade:
Yes. But you're better off with Breloom for that.

As for the concluding question countering:

Here is the threat list:
Tyranitar
Gyarados
Infernape
Azelf
Rhyperior
Electivire
Heracross
Salamence
Togekiss
Gengar
Garchomp
Raikou
Lucario
Rampardos
Tauros
Starmie
Weavile
Dugtrio
Alakazam
PorygonZ
Medicham
Staraptor
Slowbro
Jolteon
Aerodacty
Snorlax
Zapdos
Blissey
Suicune
Sceptile
Slaking
Ninjask
Metagross
Celebi
Jirachi
Manaphy

Check what Pokemon on your team can counter every single Pokemon there.

Speaking of which, a sticky about this could be useful.

[Flames of a Phoenix]

So Agiligross is Metagross with Agility, however, what else?

I'm assuming Adamant, with Meteor Mash and Earthquake?

[Near]

Get him to ~200 speed [like 100 EVs? Whatever]

Agility with whatever 3 moves you want.

I'd take Meteor Mash/Earthquake/Thunderpunch [or explosion]