After making an OU rain dance team, an NU trick room team and an OU toxic spikes team, I though I'd give the UU tier a try, since I'd never really experimented with the Pokemon in it before. Here goes:
Uxie@Light Clay
Careful (+SpD/-SpA)
Levitate
80 HP/252 SpD/176 Def
~ Reflect
~ Light Screen
~ U-turn
~ Yawn
Dual screens Uxie sets up screens for the whole team, and then either switches out of helps to force switches with yawn to help Altaria and Houndoom set up. EVs given give Uxie a massive SpD stat, and a very respectable Def stat as well. Once the screens are up, Uxie is practically impossible to KO, and so can comfortably come back in later in the game to set the screens up again. On the downside, she is complete taunt fodder.
Hitmontop@Life Orb
Adamant (+Atk/-SpA)
Technician
252 Atk/98 HP/120 Def/40 SpD
~ Mach Punch
~ Bullet Punch
~ Fake Out
~ Pursuit
Technitop stands as a brilliant revenge killer, with STAB mach punch with life orb reaching 117 power including STAB. bullet punch is there mainly for coverage, and pursuit to hit ghosts and Shedinja. just a generic Technitop set really. EVs give 'top maximum attacking power, whilst also providing some staying power.
Crawdaunt@Choice Scarf
Jolly(+Spe/-SpA)
Shell Armour
252 Atk/252 Spe/4 HP
~ Waterfall
~ Crunch
~ Brick Break
~ Rock Slide
I wanted to try out a Choice Scarf user in this team, and scarf Crawdaunt really does the job. He's always a surprise to the opposition, and the scarf makes him faster than almost everything in UU. EVs are standard, Jolly nature and speed IV to maximize speed. Waterfall and Crunch are the main STAB moves on this set, Rock Slide and Brick Break deal with other types, providing perfect coverage.
Sceptile@Choice Specs
Timid (+Spe/-Atk)
Overgrow
252 SpA/252 Spe/4 HP
~ Leaf Storm
~ Energy Ball
~ HP Ice
~ Focus Blast
Specstile was another pokemon I wanted to try out, and I am very impressed with its power. with base 120 Speed, not much outspeeds him at all, and with the SPecs boosting his already impressive SpA, very little survives a Leaf Storm. HP Ice is for Dragons and other grass types, Focus Blast is a powerful move, though I don't like the accuracy, suggestions for a replacement would be appreciated. Energy ball is for if I think Sceptile is going to be able to sweep, Leaf Storm is great for revenge killing, and is difficult to switch into. Specs boosted Leaf Storm comfortably OHKOs Walrein, Lapras and Milotic, pokemon who would otherwise give me trouble
Houndoom@Focus Sash
Timid (+Spe/-Atk)
Flash Fire
252 SpA/252 Spe/4 HP
~ Flamethrower/Fire Blast
~ Dark Pulse
~ Nasty Plot
~ ?
I had a NP Houndoom in my original party who took on the league on her own at level 81, and so I wanted to make a good one for competitive battling. Focus sash lets me set up nasty plot more easily, and helps 'Doom survive more easily. Fire Blast is for a powerful STAB attack, and Dark Pulse helps for coverage. My last move is undecided at the moment, I've been thinking about hiden power or protect, although fire-dark attacking combo gives almost perfect coverage anyway. EVs are standard, and timid nature is to boost her speed. Only drawback here is that she's often out sped by other pokes, which is never a good thing. any ideas for improvements or replacements are appreciated.
Altaria@Yache Berry
Adamant (+Atk/-SpA)
Natural Cure
16 Atk/252 HP/104 Spe/136 SpD
~ Dragon Dance
~ Dragon Claw
~ Roost
~ Aerial Ace
DD Altaria fills the last slot in my team, and once it's set up it can really sweep. Usually needs to DD twice before it's really any good, but with roost and good defences and resistances, that's not usually a problem. Dragon Claw and Aerial Ace are there for the STAB, although I'm considering changing Aerial Ace for Power Herb Sky Attack, for a really powerful STAB.
That's the lot. Any suggestions on how to improve are much appreciated :)
Thanks in Advance
TBG

Uxie@Light Clay
Careful (+SpD/-SpA)
Levitate
80 HP/252 SpD/176 Def
~ Reflect
~ Light Screen
~ U-turn
~ Yawn
Dual screens Uxie sets up screens for the whole team, and then either switches out of helps to force switches with yawn to help Altaria and Houndoom set up. EVs given give Uxie a massive SpD stat, and a very respectable Def stat as well. Once the screens are up, Uxie is practically impossible to KO, and so can comfortably come back in later in the game to set the screens up again. On the downside, she is complete taunt fodder.

Hitmontop@Life Orb
Adamant (+Atk/-SpA)
Technician
252 Atk/98 HP/120 Def/40 SpD
~ Mach Punch
~ Bullet Punch
~ Fake Out
~ Pursuit
Technitop stands as a brilliant revenge killer, with STAB mach punch with life orb reaching 117 power including STAB. bullet punch is there mainly for coverage, and pursuit to hit ghosts and Shedinja. just a generic Technitop set really. EVs give 'top maximum attacking power, whilst also providing some staying power.

Crawdaunt@Choice Scarf
Jolly(+Spe/-SpA)
Shell Armour
252 Atk/252 Spe/4 HP
~ Waterfall
~ Crunch
~ Brick Break
~ Rock Slide
I wanted to try out a Choice Scarf user in this team, and scarf Crawdaunt really does the job. He's always a surprise to the opposition, and the scarf makes him faster than almost everything in UU. EVs are standard, Jolly nature and speed IV to maximize speed. Waterfall and Crunch are the main STAB moves on this set, Rock Slide and Brick Break deal with other types, providing perfect coverage.

Sceptile@Choice Specs
Timid (+Spe/-Atk)
Overgrow
252 SpA/252 Spe/4 HP
~ Leaf Storm
~ Energy Ball
~ HP Ice
~ Focus Blast
Specstile was another pokemon I wanted to try out, and I am very impressed with its power. with base 120 Speed, not much outspeeds him at all, and with the SPecs boosting his already impressive SpA, very little survives a Leaf Storm. HP Ice is for Dragons and other grass types, Focus Blast is a powerful move, though I don't like the accuracy, suggestions for a replacement would be appreciated. Energy ball is for if I think Sceptile is going to be able to sweep, Leaf Storm is great for revenge killing, and is difficult to switch into. Specs boosted Leaf Storm comfortably OHKOs Walrein, Lapras and Milotic, pokemon who would otherwise give me trouble

Houndoom@Focus Sash
Timid (+Spe/-Atk)
Flash Fire
252 SpA/252 Spe/4 HP
~ Flamethrower/Fire Blast
~ Dark Pulse
~ Nasty Plot
~ ?
I had a NP Houndoom in my original party who took on the league on her own at level 81, and so I wanted to make a good one for competitive battling. Focus sash lets me set up nasty plot more easily, and helps 'Doom survive more easily. Fire Blast is for a powerful STAB attack, and Dark Pulse helps for coverage. My last move is undecided at the moment, I've been thinking about hiden power or protect, although fire-dark attacking combo gives almost perfect coverage anyway. EVs are standard, and timid nature is to boost her speed. Only drawback here is that she's often out sped by other pokes, which is never a good thing. any ideas for improvements or replacements are appreciated.

Altaria@Yache Berry
Adamant (+Atk/-SpA)
Natural Cure
16 Atk/252 HP/104 Spe/136 SpD
~ Dragon Dance
~ Dragon Claw
~ Roost
~ Aerial Ace
DD Altaria fills the last slot in my team, and once it's set up it can really sweep. Usually needs to DD twice before it's really any good, but with roost and good defences and resistances, that's not usually a problem. Dragon Claw and Aerial Ace are there for the STAB, although I'm considering changing Aerial Ace for Power Herb Sky Attack, for a really powerful STAB.
That's the lot. Any suggestions on how to improve are much appreciated :)
Thanks in Advance
TBG