Alcremie
- Incredible Special Defense and amazing Special Attack
- Decent Defense
- STAB attacks super effective against Piers, part of Raihan's team, and a few Pokemon in the Champion's Cup
- Learns moves like Mystical Fire, Energy Ball, and Dazzling Gleam
- Pretty slow
- Iffy HP
- May take a bit to evolve
Togekiss
- Brilliant Special Attack
- Very solid defenses
- STAB attacks super effective against Piers, part of Raihan's team, and a few Pokemon in the Champion's Cup
- Serene Grace means FlinchHax fun with Air Slash
- Learns moves like Air Slash, Flamethrower, Dazzling Gleam, and Shadow Ball
- 80 Speed is average
- Friendship evolutions are a pain
Ribombee
- Phenomenal Speed
- Respectable Special Attack
- STAB attacks super effective against Piers, part of Raihan's team, and a few Pokemon in the Champion's Cup
- Learns moves like Psychic, Bug Buzz, Dazzling Gleam, and Energy Ball
- Quite frail
I personally would use Ribombee, but Togekiss is good. I'll provide sets for all three:
Alcremie @ anything
Ability: Sweet Veil
- Dazzling Gleam
- Mystical Fire
- Energy Ball / Giga Drain
- Psychic / Calm Mind
Togekiss @ anything
Ability: Serene Grace
- Dazzling Gleam
- Shadow Ball
- Air Slash
- Flamethrower
Ribombee @ anything
Ability: Shield Dust
- Dazzling Gleam
- Bug Buzz / Pollen Puff
- Energy Ball
- Stun Spore
It should be noted that you can trade for a Togepi in Hammerlocke. The person requires a Toxel, which can easily be obtained as a gift from the Route 5 Nursery.
Hope I helped!