hey,
i recommend you switch the heatran EVs:
60 HP / 252 SAtk / 196 Spd -> 52 HP / 252 SAtk / 204 Spd
this lets him outspeed base 70 positive natured pokemon, most importantly speedy breloom (revenge sleep) and specs politoed (oneshot with solar beam, though you give them 1 free turn to setup)...