Here's some ideas for making OU pokes Uber. I made sure to mantain a few flaws, as every pokemon needs a weakness.
Alakazam
Magic Guard is excellent, and he could hardly ask for a better ability. Still, he has competetion with Mewtwo and Deoxys A, meaning he has to have his own niche in between the two. Bulkier than Deoxys A, but more class cannon than mewtwo.
OU: HP 55 Atk 50 Def 45 SpA 135 SpD 85 Spe 120
U: HP 70 Atk 50 Def 55 SpA 165 SpD 85 Spe 135
Psystrike
Blissey
Blissey is an excellent wall, and would be Uber worthy if it weren't for its miniscule defense stat. That stat should be enough for passive hits, but still exploitable. Like this, Blissey can take a few physical hits, but certainly won't be switching into huge choice banded or boosted attacks.
OU: HP 255 Atk 10 Def 10 SpA 75 SpD 135 Spe 55
U: HP 255 Atk 10 Def 55 SpA 75 SpD 135 Spe 55
Breloom
I'd rather not change Breloom's overall function, as it can allready use so many different movesets. As such I'll just push all of its stats up slightly, but mostly the defenses so it can tank resisted attacks.
OU: HP 60 Atk 130 Def 80 SpA 60 SpD 60 Spe 70
U: HP 90 Atk 150 Def 110 SpA 80 SpD 90 Spe 90
Celebi
Another pokemon that can perform a lot of functions. Defensive, offensive, support, etc. Even more so than Breloom does Celebi just want an all around boost.
OU: HP 100 Atk 100 Def 100 SpA 100 SpD 100 Spe 100
U: HP 120 Atk 120 Def 120 SpA 120 SpD 120 Spe 120
EDIT:
NU is huge. I'm looking at Smogon now, and I'm seeing
206 pokemon in there. Perhaps we should take the 1st 100 first?
Perhaps Alomomola>Kingler.
Also, should we ignore NFEs?