Here's some idea of what to look for, on each:
Lucario @ Salac Berry/Life Orb/Wise Glasses
Modest
Inner Focus
- Aura Sphere
- Shadow Ball/Dark Pulse
- Calm Mind/Dragon Pulse
- Substitute/Psychic
Special Lucario. There's two ways you can go really, as shown above. You can either go the Calm Mind/Substitute route and have the Salac Berry, or go for the coverage route and have a Life Orb instead. Note that Aura Sphere + Dark Pulse, contrary to popular belief, does NOT provide perfect coverage (Toxicroak walls you,) but Aura Sphere + Shadow Ball does. Use Dark Pulse however if you decide against Calm Mind/Substitute.
Blissey @ Leftovers
Bold
Natural Cure/Serene Grace
- Ice Beam
- Softboiled
- Aromatherapy/Thunderbolt
- Seismic Toss/Calm Mind
Calm Mind creeps onto another set with Blissey, but for generally different purposes. Blissey's Sp.Attack vastly outstrips her abysmal Attack stat, and since Ice Beam can do damage to every Pokemon in the game bar Shedinja, it becomes the attack of choice. Softboiled for healing yourself, Aromatherapy to keep your team free of status effects also, and either Seismic Toss for a consistent 100 damage every turn, or Calm Mind as mentioned earlier to boost Ice Beam's damage as well as boost your defenses. Pick Serene Grace/Thunderbolt/Calm Mind if you don't want to re-breed, since Seismic Toss and Aromatherapy will require you re-breeding.
Blaziken @ Life Orb/Muscle Band
Lonely/Hasty
Blaze
- Sky Uppercut
- Brave Bird/Shadow Claw/Earthquake
- ThunderPunch/Stone Edge
- Fire Blast/Flare Blitz
Blaziken not getting Close Combat is a travesty in my opinion, so you have to make do with Sky Uppercut for your STAB Fighting move. Otherwise, Blaziken's movepool is amazing - after having both STAB types, you can effectively mix and match the other two moves to your heart's desire. Adamant/Jolly Nature works best if you choose Flare Blitz over Fire Blast.
Gardevoir @ Choice Specs/Choice Scarf
Modest
Trace
- Psychic
- Shadow Ball/Focus Blast
- Thunderbolt
- Energy Ball/Trick
Trick is Platinum only, so you may have to wait a few months for that one. Psychic for STAB, Shadow Ball/Focus Blast for extra coverage, likewise with Thunderbolt. If you can't get Trick, have Energy Ball instead since Gardevoir doesn't get much else, unfortunately.
Finally, make sure you read that thread that LoN_Colossus posted. I've noticed you posting in other people's threads here in the Clinic giving them advice that either ranges from being poor to outright terrible. Make sure you know what you're talking about before helping others, since you may end up doing more harm than good.