Ok, I'm LOVING this gen mons, i like all these newcomers and I hope this'll be the trend.
Tapu Koko is amazing, I love how its design is complex without being overdesigned at all. Terrains as abilities are much less gimmicky and more threatening than their respective moves, and auto-electric terrain looks scary on a likely offensive mon like Tapu Koko. Nature Fury looks like a better Nature Power, it would be great as a 100BP normal move with perfect accuracy that changes depending on terrains... If so, that'd make a 150BP electric STAB for Tapu Koko. It's quite obvious that Tapu Koko is some sort of legendary or semi-legendary being a guardian (580 to 600BST), so a trio of guardians legendary with terrains abilities and Nature Fury should be expected (maybe grass/fairy and fairy? Or maybe there'll be some new terrains). A quartet is possible, but I'm expecting the 4th island being reserved for Solgaleo/Lunala.
Drampa is absolutely cute. Hope it'll get nice stat distribution, it looks like specially oriented and/or defensive. Its typing is odd, but I like it being a new combo, and if the ability counts like a sort of special only weakness policy, it could be great with the right stats and moves. If instead it activates on low health, it may be a bit more gimmicky. Both ways, I hope it'll get useful recovery.
Charjabug and Vikavolt: the first is fine and amusing as a cocoon bug, and it looks like it'll not be helpless as usual metapod clones. Vikavolt is BADASS, the first really badass early bug excluding Mega Beedrill (if it even counts, being a mega). It looks as a mix between M-Beedrill itself and M-pinsir, and that's actually pretty good. Hope it'll be physical to differentiate itself from Galvantula: those huge jaws looks promising in that regard. And I hope it'll abandon swarm for something more useful. Strong Jaw would be awesome, but even something like Motor Drive would be cool.
I don't get all the hate for Bruxish: a badass drag queen triggerfish? Awesome! Much more unique than usual fishes. Water/Psychic is ok (pure water would've been boring) and Dazzling blocking priorities is truly a fantastic ability. If it'll has a proper distribution it could greatly influence the metagame. With the right stats and movepool, Bruxish itself could be a fantastic Talonflame counter.
Cutiefly is just a mosquito OVERLOADED in cuteness. I wonder if it'll be the Zubat/Tentacool of this gen. Hope it'll get most draining moves (with some new would be better) and maybe a new draining related ability.
The pika-clone is actually one of the best pika-clones out there. Not only a cute looking hedgehog, but also with a good typing. Of course if it'll stick with the tradition of no evos it'll likely never see the light of upper tiers, but it has the potential of being better than its counterparts.