On Milotic, those 8 speed EVs are not needed in OU as in UU they're for outspeeding max speed base 50s. Have you considered an EV Spread of 252 HP/ 240 Def/ 16 SpD? It insures that you aren't 2hkoed by any unboosted attacks i.e. LO Heatran's HP Grass maxes at 44.7%, LO Starmie's Thunderbolt maxes at 49%, and LO Gengar's Shadow Ball does 32-38%. You should also consider running HP Electric over Haze to deal with Gyarados better who would otherwise fuck over the rest of your team.
If I were you, I would probably use LO Heatran over Shaymin and Milotic. He has much better synergy with them than Moltres, and is a hell lot more powerful (not to mencion bulkier!).
Heatran@Life Orb
Nature: Timid
EVs: 252 SpA/ 4 SpD/ 252 Spe
- Fire Blast
- Earth Power
- HP Grass
- Taunt
Taunt fucks Blissey while Fire/Ground/Grass covers pretty much all of OU.
Qwilfish might be good in UU, but in OU every lead fucks it over. I'd like to suggest Colbur Berry Azelf.
Azelf@Colbur Berry
Nature: Jolly
EVs: 252 HP/ 40 Atk/ 216 Spe
- Taunt
- Stealth Rock
- U-turn
- Explosion
This Azelf handles every lead well bar Specs Heatran and Scarf Jirachi. He's basically like Qwilfish but not as crappy.
You COULD replace Donphan with Starmie and Milotic with Rotom-A. However, that would make you really Pursuit weak so it's your decision really.