I picked these because I thought of them first.
>Ariados
>Abilities: Prankster(+), Insomnia / Sniper (HA)
>Defense: 70 -> 90 (+20)
>SpDef: 70 -> 90 (+20)
>BST: 400 -> 440 (+20)
Still not great, but now it has a fun new gimmick: Priority Toxic Threads and Spider Webs! Also, it can maybe take a hit in-game and not instantly die.
>Mightyena
>Attack: 90 -> 100 (+10)
>SpAtk: 60 -> 50 (-10)
>Speed: 70 -> 90 (+10)
>New Moves: Pursuit
Nothing amazing. 100 is acceptable for something with this small a movepool. Pursuit is because it's a fucking hyena but somehow doesn't learn it already.
>Kricketune
>Attack: 85 -> 95 (+10)
>SpAtk: 55 -> 45 (-10)
>Speed: 65 -> 95 (+30)
>BST: 384 -> 414
Still not great, but at least now it's an acceptably quick glass cannon. Can't go too crazy; it still evolves at Level 10.
>Watchog
>Attack: 85 -> 75 (-15)
>SpAtk: 60 -> 85 (+25)
>BST: 420 -> 440 (+20)
>Illuminate now works like Intimidate, but for Accuracy
Watchog actually has a nice special movepool it normally can't use. By making it focus on SpAtk, we not only let it access its superior special movepool, but differentiate it from every other regional rodent, which are all physical. Illuminate's change isn't strictly for Watchog, but a lot of Abilities had functionality changes in Gen 5.
>Unfezant
>Attack: 115 -> 65 (-50)
>SpAtk: 65 -> 115 (+50)
If you never evolve your Pidove, its SOLE physical attack until Level 44 (Sky Attack) is Quick Attack. Literally every other move it learns on its own is either a special attack or a status move. It has no physical movepool. Its special movepool is marginally better. They gave it an irrelevant buff to its Attack in Gen 6, because they completely missed what the actual problem was.
>Toucannon
>HP: 80 -> 90 (+10)
>Defense: 75 -> 90 (+15)
>SpAtk: 75 -> 60 (-25)
Rather than just make Toucannon faster, we embrace its concept. Buffing its HP and Defense helps support Beak Blast's gimmick. Choice Scarf is always an option if you want to run Skill Link.