Pokemon: Cherrim
New typing: Grass -> Grass (Normal), Grass/Fire (Sunshine)
New Abilities: N/A
New Moves: Play Rough, Solar Blade, Flame Burst, Charm
Niche: If you're gonna have an ability that boosts your Attack despite having 60 base Attack, might as well make good use of it. Combined the buff to Flower Gift that hopefully wins, Cherrim enters battle with 328 Attack with max Attack and a neutral nature, which is equivalent to Adamant base 100, which isn't too shabby. This combined with a dangerous STAB combo in Solar Blade and Sun-boosted Storm Strike makes Cherrim a pretty threatening Swords Dance sweeper. Or, there's still the possibility of running a special set, as, even off of just 85 Special Attack, Solar Beam, Weather Ball, and Dazzling Gleam will hurt while being able to set up with Growth.
Pokemon: Buizel line
New typing: Water (Buizel) -> Water/Fighting
New Abilities: N/A
New Moves: Double Kick, Drain Punch, Knock Off (Floatzel only), Reversal, Endeavor, Seismic Toss
Niche: Out of all the things that got Technician, the Buizel line have had it the worst by far. Time to fix that. Give it some Tech-boosted Fighting moves in Double Kick and Drain Punch and make them STAB on Floatzel and Tech-boosted Knock Off and that's probably all you need to make this at least a UU threat. Slap a Choice Band or Anguish Bandanna on this and go to town.
Pokemon: Clamperl's Parents
New typing: Water -> Water/Fairy (Gorebyss), Water/Dark (Huntail)
New Abilities: Huntail - Strong Jaw (HA: Replaces Water Veil)
New Moves:
Gorebyss - Moonblast, Dazzling Gleam, Sweet Kiss, Charm, Hyper Voice, Play Rough, Dark Pulse
Huntail - Payback, Foul Play, Taunt, Pursuit, Hyper Voice, Dark Pulse, Play Rough
Niche: When I gave Gorebyss Liquid Voice, part of the plan was also buffing it to have Hyper Voice. That didn't work, so take 2. Also, Water/Fairy and Water/Dark coverage + Shell Smash is super interesting.
Pokemon: Sentret line
New typing: Normal -> Fairy
New Abilities: Cute Charm (Replaces Keen Eye), Pixilate (Replaces Frisk)
New Moves: Play Rough, Fairy Lock, Slack Off, Laser Focus, Draining Kiss, Sweet Kiss
Niche: How can I make Furret useful in a mod where you can't change stats. How about a new better typing, Pixilate-boosted Returns, Quick Attacks, and unblockable Super Fangs, recovery, and the fact that Furret already has a ridiculously good movepool for what it is (Coil, Elemental Punches, Knock Off, Brick Break, Agility, Aqua Tail, U-Turn, Sucker Punch) and all of sudden, you do not want to be on the bad side of this cute little thing. Crazy what a couple buffs can do to such bad stats.